Sample records for target volume fast

  1. [Target volume margins for lung cancer: internal target volume/clinical target volume].

    PubMed

    Jouin, A; Pourel, N

    2013-10-01

    The aim of this study was to carry out a review of margins that should be used for the delineation of target volumes in lung cancer, with a focus on margins from gross tumour volume (GTV) to clinical target volume (CTV) and internal target volume (ITV) delineation. Our review was based on a PubMed literature search with, as a cornerstone, the 2010 European Organisation for Research and Treatment of Cancer (EORTC) recommandations by De Ruysscher et al. The keywords used for the search were: radiotherapy, lung cancer, clinical target volume, internal target volume. The relevant information was categorized under the following headings: gross tumour volume definition (GTV), CTV-GTV margin (first tumoural CTV then nodal CTV definition), in field versus elective nodal irradiation, metabolic imaging role through the input of the PET scanner for tumour target volume and limitations of PET-CT imaging for nodal target volume definition, postoperative radiotherapy target volume definition, delineation of target volumes after induction chemotherapy; then the internal target volume is specified as well as tumoural mobility for lung cancer and respiratory gating techniques. Finally, a chapter is dedicated to planning target volume definition and another to small cell lung cancer. For each heading, the most relevant and recent clinical trials and publications are mentioned. Copyright © 2013. Published by Elsevier SAS.

  2. Investigating different computed tomography techniques for internal target volume definition.

    PubMed

    Yoganathan, S A; Maria Das, K J; Subramanian, V Siva; Raj, D Gowtham; Agarwal, Arpita; Kumar, Shaleen

    2017-01-01

    The aim of this work was to evaluate the various computed tomography (CT) techniques such as fast CT, slow CT, breath-hold (BH) CT, full-fan cone beam CT (FF-CBCT), half-fan CBCT (HF-CBCT), and average CT for delineation of internal target volume (ITV). In addition, these ITVs were compared against four-dimensional CT (4DCT) ITVs. Three-dimensional target motion was simulated using dynamic thorax phantom with target insert of diameter 3 cm for ten respiration data. CT images were acquired using a commercially available multislice CT scanner, and the CBCT images were acquired using On-Board-Imager. Average CT was generated by averaging 10 phases of 4DCT. ITVs were delineated for each CT by contouring the volume of the target ball; 4DCT ITVs were generated by merging all 10 phases target volumes. Incase of BH-CT, ITV was derived by boolean of CT phases 0%, 50%, and fast CT target volumes. ITVs determined by all CT and CBCT scans were significantly smaller (P < 0.05) than the 4DCT ITV, whereas there was no significant difference between average CT and 4DCT ITVs (P = 0.17). Fast CT had the maximum deviation (-46.1% ± 20.9%) followed by slow CT (-34.3% ± 11.0%) and FF-CBCT scans (-26.3% ± 8.7%). However, HF-CBCT scans (-12.9% ± 4.4%) and BH-CT scans (-11.1% ± 8.5%) resulted in almost similar deviation. On the contrary, average CT had the least deviation (-4.7% ± 9.8%). When comparing with 4DCT, all the CT techniques underestimated ITV. In the absence of 4DCT, the HF-CBCT target volumes with appropriate margin may be a reasonable approach for defining the ITV.

  3. Tri-FAST Hardware-in-the-Loop Simulation. Volume I. Tri-FAST Hardware-in-the-Loop Simulation at the Advanced Simulation Center

    DTIC Science & Technology

    1979-03-28

    TECHNICAL REPORT T-79-43 TRI- FAST HARDWARE-IN-THE-LOOP SIMULATION Volume 1: Trn FAST Hardware-In-the. Loop Simulation at the Advanced Simulation...Identify by block number) Tri- FAST Hardware-in-the-Loop ACSL Advanced Simulation Center Simulation RF Target Models I a. AfIACT ( sin -oveme skit N nem...e n tdositr by block number) The purpose of this report is to document the Tri- FAST missile simulation development and the seeker hardware-in-the

  4. Feasibility of large volume tumor ablation using multiple-mode strategy with fast scanning method: A numerical study

    NASA Astrophysics Data System (ADS)

    Wu, Hao; Shen, Guofeng; Qiao, Shan; Chen, Yazhu

    2017-03-01

    Sonication with fast scanning method can generate homogeneous lesions without complex planning. But when the target region is large, switching focus too fast will reduce the heat accumulation, the margin of which may not ablated. Furthermore, high blood perfusion rate will reduce this maximum volume that can be ablated. Therefore, fast scanning method may not be applied to large volume tumor. To expand the therapy scope, this study combines the fast scan method with multiple mode strategy. Through simulation and experiment, the feasibility of this new strategy is evaluated and analyzed.

  5. Fasting target for hyperglycaemia in pregnancy.

    PubMed

    Moses, Robert G; Wong, Veronica C K; Lambert, Kelly; Morris, Gary J

    2016-10-01

    Knowledge of the fasting plasma glucose of healthy women may assist in the setting of treatment targets for women with hyperglycaemia in pregnancy (HIP). This study examines the pregnancy glucose tolerance test results of 3344 women without HIP collected over a three-year period. The median fasting plasma glucose was 4.4 mmol/L with an interquartile range of 4.2-4.6 mmol/L and a 5th to 95th centile of 3.8-4.9 mmol/L. As the diagnostic fasting glucose level for HIP is ≥5.1 mmol/L, these data support a treatment target of ≤5.0 mmol/L. © 2016 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  6. Fast Electron Deposition in Laser Shock Compressed Plastic Targets

    NASA Astrophysics Data System (ADS)

    Hall, T. A.; Ellwi, S.; Batani, D.; Bernardinello, A.; Masella, V.; Koenig, M.; Benuzzi, A.; Krishnan, J.; Pisani, F.; Djaoui, A.; Norreys, P.; Neely, D.; Rose, S.; Key, M. H.; Fews, P.

    1998-08-01

    We present the first results of fast electron deposition in a laser shock compressed plasma. The interaction of a 3 ps, 15 J laser pulse with solid polyethylene targets is used to produce fast electrons on one side of foil targets and a 2 ns duration laser pulse is used to drive a shock wave into the target from the opposite side. Kα emission from chlorine fluor buried layers is used to measure the electron transport. The hot electron range in the shock compressed plastic is found to be approximately twice as large as the range in the solid density plastic.

  7. Compression Dynamics of an Indirect Drive Fast Ignition Target

    NASA Astrophysics Data System (ADS)

    Stephens, R. B.; Hatchett, S. A.; Turner, R. E.; Tanaka, K. A.; Kodama, R.; Soures, J.

    2002-11-01

    We have compared the compression of an indirectly driven cone-in-shell target, a type proposed for the fast ignition concept, with models. The experimental parameters -500 μm diameter plastic shell with 60 μm thick wall were a 1/5 scale realization of a fast ignition target designed for NIF (absorbing 180 kJ for compression and ˜30 kJ for ignition, and yielding ˜30 MJ) [1]. The implosion was backlit with 6.4 keV x-rays, and observed with a framing camera which captured the implosion from ˜2.6 to 3.3 ns after the onset. The collapsing structure was very similar to model predictions except that non-thermal m-band emissions from the hohlraum penetrated the shell and vaporized gold off the reentrant cone. This could be eliminated by changing the hohlraum composition. [1] S. Hatchett, et al., 5th Wkshp on Fast Ignition of Fusion Targets (Satellite Wkshp, 28th EPS Conf. on Contr. Fusion and Plasma Phys.), Madeira, Portugal (2001).

  8. A Fast MEANSHIFT Algorithm-Based Target Tracking System

    PubMed Central

    Sun, Jian

    2012-01-01

    Tracking moving targets in complex scenes using an active video camera is a challenging task. Tracking accuracy and efficiency are two key yet generally incompatible aspects of a Target Tracking System (TTS). A compromise scheme will be studied in this paper. A fast mean-shift-based Target Tracking scheme is designed and realized, which is robust to partial occlusion and changes in object appearance. The physical simulation shows that the image signal processing speed is >50 frame/s. PMID:22969397

  9. Secure FAST: Security Enhancement in the NATO Time Sensitive Targeting Tool

    DTIC Science & Technology

    2010-11-01

    designed to aid in the tracking and prosecuting of Time Sensitive Targets. The FAST tool provides user level authentication and authorisation in terms...level authentication and authorisation in terms of security. It uses operating system level security but does not provide application level security for...and collaboration tool, designed to aid in the tracking and prosecuting of Time Sensitive Targets. The FAST tool provides user level authentication and

  10. Timescale Halo: Average-Speed Targets Elicit More Positive and Less Negative Attributions than Slow or Fast Targets

    PubMed Central

    Hernandez, Ivan; Preston, Jesse Lee; Hepler, Justin

    2014-01-01

    Research on the timescale bias has found that observers perceive more capacity for mind in targets moving at an average speed, relative to slow or fast moving targets. The present research revisited the timescale bias as a type of halo effect, where normal-speed people elicit positive evaluations and abnormal-speed (slow and fast) people elicit negative evaluations. In two studies, participants viewed videos of people walking at a slow, average, or fast speed. We find evidence for a timescale halo effect: people walking at an average-speed were attributed more positive mental traits, but fewer negative mental traits, relative to slow or fast moving people. These effects held across both cognitive and emotional dimensions of mind and were mediated by overall positive/negative ratings of the person. These results suggest that, rather than eliciting greater perceptions of general mind, the timescale bias may reflect a generalized positivity toward average speed people relative to slow or fast moving people. PMID:24421882

  11. Improving the consistency in cervical esophageal target volume definition by special training.

    PubMed

    Tai, Patricia; Van Dyk, Jake; Battista, Jerry; Yu, Edward; Stitt, Larry; Tonita, Jon; Agboola, Olusegun; Brierley, James; Dar, Rashid; Leighton, Christopher; Malone, Shawn; Strang, Barbara; Truong, Pauline; Videtic, Gregory; Wong, C Shun; Wong, Rebecca; Youssef, Youssef

    2002-07-01

    Three-dimensional conformal radiation therapy requires the precise definition of the target volume. Its potential benefits could be offset by the inconsistency in target definition by radiation oncologists. In a previous survey of radiation oncologists, a large degree of variation in target volume definition of cervical esophageal cancer was noted for the boost phase of radiotherapy. The present study evaluated whether special training could improve the consistency in target volume definitions. A pre-training survey was performed to establish baseline values. This was followed by a special one-on-one training session on treatment planning based on the RTOG 94-05 protocol to 12 radiation oncologists. Target volumes were redrawn immediately and at 1-2 months later. Post-training vs. pre-training target volumes were compared. There was less variability in the longitudinal positions of the target volumes post-training compared to pre-training (p < 0.05 in 5 of 6 comparisons). One case had more variability due to the lack of a visible gross tumor on CT scans. Transverse contours of target volumes did not show any significant difference pre- or post-training. For cervical esophageal cancer, this study suggests that special training on protocol guidelines may improve consistency in target volume definition. Explicit protocol directions are required for situations where the gross tumor is not easily visible on CT scans. This may be particularly important for multicenter clinical trials, to reduce the occurrences of protocol violations.

  12. TomoEED: Fast Edge-Enhancing Denoising of Tomographic Volumes.

    PubMed

    Moreno, J J; Martínez-Sánchez, A; Martínez, J A; Garzón, E M; Fernández, J J

    2018-05-29

    TomoEED is an optimized software tool for fast feature-preserving noise filtering of large 3D tomographic volumes on CPUs and GPUs. The tool is based on the anisotropic nonlinear diffusion method. It has been developed with special emphasis in the reduction of the computational demands by using different strategies, from the algorithmic to the high performance computing perspectives. TomoEED manages to filter large volumes in a matter of minutes in standard computers. TomoEED has been developed in C. It is available for Linux platforms at http://www.cnb.csic.es/%7ejjfernandez/tomoeed. gmartin@ual.es, JJ.Fernandez@csic.es. Supplementary data are available at Bioinformatics online.

  13. Simulations of electron transport and ignition for direct-drive fast-ignition targets

    NASA Astrophysics Data System (ADS)

    Solodov, A. A.; Anderson, K. S.; Betti, R.; Gotcheva, V.; Myatt, J.; Delettrez, J. A.; Skupsky, S.; Theobald, W.; Stoeckl, C.

    2008-11-01

    The performance of high-gain, fast-ignition fusion targets is investigated using one-dimensional hydrodynamic simulations of implosion and two-dimensional (2D) hybrid fluid-particle simulations of hot-electron transport, ignition, and burn. The 2D/3D hybrid-particle-in-cell code LSP [D. R. Welch et al., Nucl. Instrum. Methods Phys. Res. A 464, 134 (2001)] and the 2D fluid code DRACO [P. B. Radha et al., Phys. Plasmas 12, 056307 (2005)] are integrated to simulate the hot-electron transport and heating for direct-drive fast-ignition targets. LSP simulates the transport of hot electrons from the place where they are generated to the dense fuel core where their energy is absorbed. DRACO includes the physics required to simulate compression, ignition, and burn of fast-ignition targets. The self-generated resistive magnetic field is found to collimate the hot-electron beam, increase the coupling efficiency of hot electrons with the target, and reduce the minimum energy required for ignition. Resistive filamentation of the hot-electron beam is also observed. The minimum energy required for ignition is found for hot electrons with realistic angular spread and Maxwellian energy-distribution function.

  14. Fast cat-eye effect target recognition based on saliency extraction

    NASA Astrophysics Data System (ADS)

    Li, Li; Ren, Jianlin; Wang, Xingbin

    2015-09-01

    Background complexity is a main reason that results in false detection in cat-eye target recognition. Human vision has selective attention property which can help search the salient target from complex unknown scenes quickly and precisely. In the paper, we propose a novel cat-eye effect target recognition method named Multi-channel Saliency Processing before Fusion (MSPF). This method combines traditional cat-eye target recognition with the selective characters of visual attention. Furthermore, parallel processing enables it to achieve fast recognition. Experimental results show that the proposed method performs better in accuracy, robustness and speed compared to other methods.

  15. LLE Review Quarterly Report (October - December 2007). Volume 113

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zuegel, Jonathan D.

    2007-12-01

    This volume of the LLE Review, covering October–December 2007, features “High-Intensity Laser–Plasma Interactions in the Refluxing Limit,” by P. M. Nilson, W. Theobald, J. Myatt, C. Stoeckl, M. Storm, O. V. Gotchev, J. D. Zuegel, R. Betti, D. D. Meyerhofer, and T. C. Sangster. In this article (p. 1), the authors report on target experiments using the Multi-Terawatt (MTW) Laser Facility to study isochoric heating of solid-density targets by fast electrons produced from intense, short-pulse laser irradiation. Electron refluxing occurs due to target-sheath field effects and contains most of the fast electrons within the target volume. This efficiently heats themore » solid-density plasma through collisions. X-ray spectroscopic measurements of absolute K α (x-radiation) photon yields and variations of the K β/K α b emission ratio both indicate that laser energy couples to fast electrons with a conversion efficiency of approximately 20%. Bulk electron temperatures of at least 200 eV are inferred for the smallest mass targets.« less

  16. OPS MCC level B/C formulation requirements: Area targets and space volumes processor

    NASA Technical Reports Server (NTRS)

    Bishop, M. J., Jr.

    1979-01-01

    The level B/C mathematical specifications for the area targets and space volumes processor (ATSVP) are described. The processor is designed to compute the acquisition-of-signal (AOS) and loss-of-signal (LOS) times for area targets and space volumes. The characteristics of the area targets and space volumes are given. The mathematical equations necessary to determine whether the spacecraft lies within the area target or space volume are given. These equations provide a detailed model of the target geometry. A semianalytical technique for predicting the AOS and LOS time periods is disucssed. This technique was designed to bound the actual visibility period using a simplified target geometry model and unperturbed orbital motion. Functional overview of the ATSVP is presented and it's detailed logic flow is described.

  17. Diffusion of external magnetic fields into the cone-in-shell target in the fast ignition

    NASA Astrophysics Data System (ADS)

    Sunahara, Atsushi; Morita, Hiroki; Johzaki, Tomoyuki; Nagatomo, Hideo; Fujioka, Shinsuke; Hassanein, Ahmed; Firex Project Team

    2017-10-01

    We simulated the diffusion of externally applied magnetic fields into cone-in-shell target in the fast ignition. Recently, in the fast ignition scheme, the externally magnetic fields up to kilo-Tesla is used to guide fast electrons to the high-dense imploded core. In order to study the profile of the magnetic field, we have developed 2D cylindrical Maxwell equation solver with Ohm's law, and carried out simulations of diffusion of externally applied magnetic fields into a cone-in-shell target. We estimated the conductivity of the cone and shell target based on the assumption of Saha-ionization equilibrium. Also, we calculated the temporal evolution of the target temperature heated by the eddy current driven by temporal variation of magnetic fields, based on the accurate equation of state. Both, the diffusion of magnetic field and the increase of target temperature interact with each other. We present our results of temporal evolution of the magnetic field and its diffusion into the cone and shell target.

  18. Characterization of the fast electrons distribution produced in a high intensity laser target interaction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Westover, B.; Lawrence Livermore National Laboratory, Livermore, California 94550; Chen, C. D.

    2014-03-15

    Experiments on the Titan laser (∼150 J, 0.7 ps, 2 × 10{sup 20} W cm{sup −2}) at the Lawrence Livermore National Laboratory were carried out in order to study the properties of fast electrons produced by high-intensity, short pulse laser interacting with matter under conditions relevant to Fast Ignition. Bremsstrahlung x-rays produced by these fast electrons were measured by a set of compact filter-stack based x-ray detectors placed at three angles with respect to the target. The measured bremsstrahlung signal allows a characterization of the fast electron beam spectrum, conversion efficiency of laser energy into fast electron kinetic energy and angular distribution. A Monte Carlo codemore » Integrated Tiger Series was used to model the bremsstrahlung signal and infer a laser to fast electron conversion efficiency of 30%, an electron slope temperature of about 2.2 MeV, and a mean divergence angle of 39°. Simulations were also performed with the hybrid transport code ZUMA which includes fields in the target. In this case, a conversion efficiency of laser energy to fast electron energy of 34% and a slope temperature between 1.5 MeV and 4 MeV depending on the angle between the target normal direction and the measuring spectrometer are found. The observed temperature of the bremsstrahlung spectrum, and therefore the inferred electron spectrum are found to be angle dependent.« less

  19. Fast software-based volume rendering using multimedia instructions on PC platforms and its application to virtual endoscopy

    NASA Astrophysics Data System (ADS)

    Mori, Kensaku; Suenaga, Yasuhito; Toriwaki, Jun-ichiro

    2003-05-01

    This paper describes a software-based fast volume rendering (VolR) method on a PC platform by using multimedia instructions, such as SIMD instructions, which are currently available in PCs' CPUs. This method achieves fast rendering speed through highly optimizing software rather than an improved rendering algorithm. In volume rendering using a ray casting method, the system requires fast execution of the following processes: (a) interpolation of voxel or color values at sample points, (b) computation of normal vectors (gray-level gradient vectors), (c) calculation of shaded values obtained by dot-products of normal vectors and light source direction vectors, (d) memory access to a huge area, and (e) efficient ray skipping at translucent regions. The proposed software implements these fundamental processes in volume rending by using special instruction sets for multimedia processing. The proposed software can generate virtual endoscopic images of a 3-D volume of 512x512x489 voxel size by volume rendering with perspective projection, specular reflection, and on-the-fly normal vector computation on a conventional PC without any special hardware at thirteen frames per second. Semi-translucent display is also possible.

  20. Fast multiview three-dimensional reconstruction method using cost volume filtering

    NASA Astrophysics Data System (ADS)

    Lee, Seung Joo; Park, Min Ki; Jang, In Yeop; Lee, Kwan H.

    2014-03-01

    As the number of customers who want to record three-dimensional (3-D) information using a mobile electronic device increases, it becomes more and more important to develop a method which quickly reconstructs a 3-D model from multiview images. A fast multiview-based 3-D reconstruction method is presented, which is suitable for the mobile environment by constructing a cost volume of the 3-D height field. This method consists of two steps: the construction of a reliable base surface and the recovery of shape details. In each step, the cost volume is constructed using photoconsistency and then it is filtered according to the multiscale. The multiscale-based cost volume filtering allows the 3-D reconstruction to maintain the overall shape and to preserve the shape details. We demonstrate the strength of the proposed method in terms of computation time, accuracy, and unconstrained acquisition environment.

  1. Combined Recipe for Clinical Target Volume and Planning Target Volume Margins

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stroom, Joep, E-mail: joep.stroom@fundacaochampalimaud.pt; Gilhuijs, Kenneth; Vieira, Sandra

    2014-03-01

    Purpose: To develop a combined recipe for clinical target volume (CTV) and planning target volume (PTV) margins. Methods and Materials: A widely accepted PTV margin recipe is M{sub geo} = aΣ{sub geo} + bσ{sub geo}, with Σ{sub geo} and σ{sub geo} standard deviations (SDs) representing systematic and random geometric uncertainties, respectively. On the basis of histopathology data of breast and lung tumors, we suggest describing the distribution of microscopic islets around the gross tumor volume (GTV) by a half-Gaussian with SD Σ{sub micro}, yielding as possible CTV margin recipe: M{sub micro} = ƒ(N{sub i}) × Σ{sub micro}, with N{sub i}more » the average number of microscopic islets per patient. To determine ƒ(N{sub i}), a computer model was developed that simulated radiation therapy of a spherical GTV with isotropic distribution of microscopic disease in a large group of virtual patients. The minimal margin that yielded D{sub min} <95% in maximally 10% of patients was calculated for various Σ{sub micro} and N{sub i}. Because Σ{sub micro} is independent of Σ{sub geo}, we propose they should be added quadratically, yielding for a combined GTV-to-PTV margin recipe: M{sub GTV-PTV} = √([aΣ{sub geo}]{sup 2} + [ƒ(N{sub i})Σ{sub micro}]{sup 2}) + bσ{sub geo}. This was validated by the computer model through numerous simultaneous simulations of microscopic and geometric uncertainties. Results: The margin factor ƒ(N{sub i}) in a relevant range of Σ{sub micro} and N{sub i} can be given by: ƒ(N{sub i}) = 1.4 + 0.8log(N{sub i}). Filling in the other factors found in our simulations (a = 2.1 and b = 0.8) yields for the combined recipe: M{sub GTV-PTV} = √((2.1Σ{sub geo}){sup 2} + ([1.4 + 0.8log(N{sub i})] × Σ{sub micro}){sup 2}) + 0.8σ{sub geo}. The average margin difference between the simultaneous simulations and the above recipe was 0.2 ± 0.8 mm (1 SD). Calculating M{sub geo} and M{sub micro} separately and adding them linearly overestimated PTVs

  2. Higher fasting plasma glucose is associated with smaller striatal volume and poorer fine motor skills in a longitudinal cohort.

    PubMed

    Zhang, Tianqi; Shaw, Marnie E; Walsh, Erin I; Sachdev, Perminder S; Anstey, Kaarin J; Cherbuin, Nicolas

    2018-06-07

    Previous studies have demonstrated associations between higher blood glucose and brain atrophy and functional deficits, however, little is known about the association between blood glucose, striatal volume and striatal function despite sensori-motor deficits being reported in diabetes. This study investigated the relationship between blood glucose levels, striatal volume and fine motor skills in a longitudinal cohort of cognitively healthy individuals living in the community with normal or impaired fasting glucose or type 2 diabetes. Participants were 271 cognitively healthy individuals (mean age 63 years at inclusion) with normal fasting glucose levels (<5.6 mmol/L) (n=173), impaired fasting glucose (5.6-6.9 mmol/L) (n=57), or with type 2 diabetes (≥7.0 mmol/L) (n=41). Fasting glucose, Purdue Pegboard scores as measurement of fine motor skills, and brain scans were collected at wave 1, 2 and 4, over a total follow-up of twelve years. Striatal volumes were measured using FreeSurfer after controlling for age, sex and intracranial volume. Results showed that type 2 diabetes was associated with smaller right putamen volume and lower Purdue Pegboard scores after controlling for age, sex and intracranial volume. These findings add to the evidence suggesting that higher blood glucose levels, especially type 2 diabetes, may impair brain structure and function. Copyright © 2018. Published by Elsevier B.V.

  3. Stereotactic ultrasound for target volume definition in a patient with prostate cancer and bilateral total hip replacement.

    PubMed

    Boda-Heggemann, Judit; Haneder, Stefan; Ehmann, Michael; Sihono, Dwi Seno Kuncoro; Wertz, Hansjörg; Mai, Sabine; Kegel, Stefan; Heitmann, Sigrun; von Swietochowski, Sandra; Lohr, Frank; Wenz, Frederik

    2015-01-01

    the isocenter of the CT simulator and acquired with intermodal online coregistration directly at the planning CT is a fast and easy method to reliably delineate the prostate and target volumes and for daily IGRT. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  4. Failure Analysis by Statistical Techniques (FAST). Volume 1. User’s Manual

    DTIC Science & Technology

    1974-10-31

    REPORT NUMBER DNA 3336F-1 2. OOVT ACCESSION NO 4. TITLE Cand Sublllle) • FAILURE ANALYSIS BY STATISTICAL TECHNIQUES (FAST) Volume I, User’s...SS2), and t’ a facility ( SS7 ). The other three diagrams break down the three critical subsystems. T le median probability of survival of the

  5. Gastric pH and residual volume after 1 and 2 h fasting time for clear fluids in children†.

    PubMed

    Schmidt, A R; Buehler, P; Seglias, L; Stark, T; Brotschi, B; Renner, T; Sabandal, C; Klaghofer, R; Weiss, M; Schmitz, A

    2015-03-01

    Current guidelines suggest a fasting time of 2 h for clear fluids, which is often exceeded in clinical practice, leading to discomfort, dehydration and stressful anaesthesia induction to patients, especially in the paediatric population. Shorter fluid fasting might be a strategy to improve patient comfort but has not been investigated yet. This prospective clinical trial compares gastric pH and residual volume after 1 vs 2 h of preoperative clear fluid fasting. Children (1-16 yr, ASA I or II) undergoing elective procedures in general anaesthesia requiring tracheal intubation were randomized into group A with 60 min or B with 120 min preoperative clear fluid fasting. To determine gastric pH and residual volume, the gastric content was sampled in supine, left and right lateral patient position using an oro-gastric tube after intubation. Data are median (interquartile range) for group A or B (P<0.05). In total, 131 children aged 1.01-16.23 yr were included; gastric pH was determined in 120 cases. Patient characteristic data were similar between the two groups, except for gender (46/33 males in group A/B; P=0.02). Despite significantly shorter fasting times for clear fluids in group A compared with group B (76/136 min; P<0.001), no significant difference was observed regarding gastric pH [1.43 (1.30-1.56)/1.44 (1.29-1.68), P=0.66] or residual volume [0.43 (0.21-0.84)/0.46 (0.19-0.78) ml kg(-1), P=0.47]. One hour clear fluid fasting does not alter gastric pH or residual volume significantly compared with 2 h fasting. The study was approved by the local ethics committee (KEK-ZH-Nr. 2011-0034) and registered with ClinicalTrials.gov (NCT01516775). © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Evaluation of the effect of Islamic fasting on lung volumes and capacities in the healthy persons.

    PubMed

    Moosavi, Seyyed-Ali J; Kabir, Ali; Moghimi, Ali; Chehrei, Ali; Rad, Mohammad B

    2007-11-01

    To evaluate the changes in pulmonary volumes during and after Islamic fasting. It is a cohort study conducted on 117 healthy subjects selected on a random basis from employees, professors and students of Iran University of Medical Sciences, Tehran, Iran, between December 1999 and January 2000. All of them underwent spirometry 10 days prior to Ramadan, 2 times during Ramadan, and one time 10 days post-Ramadan. In first visit, in addition to spirometry they underwent medical examination to make sure they are healthy. All of their spirometries and background information were collected. Repeated measurements analysis of variance method was used to compare the measurements. Approximately 69% of subjects were male and the mean age was 23.9 years. Mean fasting time was 27.8 days. The mean difference in forced expiratory volume in 1 second (FEV1%) was significant between the 4 visits (p=0.01). The mean FEV1% increased both during fasting and after Ramadan (p=0.017). The mean vital capacity and peak expiratory flow rate values increased during Ramadan significantly (p=0.043, p<0.001). Although the mean maximum mid-expiratory flow decreased in the beginning of Ramadan and significantly increased subsequently (p=0.02), MEF50% (p=0.004) and MEF75% (p=0.047) increased in the beginning of Ramadan and decreased subsequently. As a whole, fasting increases lung volumes and might improve pulmonary function. This finding seems to be relevant to the changes in weight during Ramadan.

  7. Evidence of locally enhanced target heating due to instabilities of counter-streaming fast electron beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koester, Petra; Cecchetti, Carlo A.; Booth, Nicola

    2015-02-15

    The high-current fast electron beams generated in high-intensity laser-solid interactions require the onset of a balancing return current in order to propagate in the target material. Such a system of counter-streaming electron currents is unstable to a variety of instabilities such as the current-filamentation instability and the two-stream instability. An experimental study aimed at investigating the role of instabilities in a system of symmetrical counter-propagating fast electron beams is presented here for the first time. The fast electron beams are generated by double-sided laser-irradiation of a layered target foil at laser intensities above 10{sup 19 }W/cm{sup 2}. High-resolution X-ray spectroscopy ofmore » the emission from the central Ti layer shows that locally enhanced energy deposition is indeed achieved in the case of counter-propagating fast electron beams.« less

  8. Filamentation instability of a fast electron beam in a dielectric target.

    PubMed

    Debayle, A; Tikhonchuk, V T

    2008-12-01

    High-intensity laser-matter interaction is an efficient method for high-current relativistic electron beam production. At current densities exceeding a several kA microm{-2} , the beam propagation is maintained by an almost complete current neutralization by the target electrons. In such a geometry of two oppositely directed flows, beam instabilities can develop, depending on the target and the beam parameters. The present paper proposes an analytical description of the filamentation instability of an electron beam propagating through an insulator target. It is shown that the collisionless and resistive instabilities enter into competition with the ionization instability. This latter process is dominant in insulator targets where the field ionization by the fast beam provides free electrons for the neutralization current.

  9. Quantification of gastrointestinal liquid volumes and distribution following a 240 mL dose of water in the fasted state.

    PubMed

    Mudie, Deanna M; Murray, Kathryn; Hoad, Caroline L; Pritchard, Susan E; Garnett, Martin C; Amidon, Gordon L; Gowland, Penny A; Spiller, Robin C; Amidon, Gregory E; Marciani, Luca

    2014-09-02

    The rate and extent of drug dissolution and absorption from solid oral dosage forms is highly dependent upon the volumes and distribution of gastric and small intestinal water. However, little is known about the time courses and distribution of water volumes in vivo in an undisturbed gut. Previous imaging studies offered a snapshot of water distribution in fasted humans and showed that water in the small intestine is distributed in small pockets. This study aimed to quantify the volume and number of water pockets in the upper gut of fasted healthy humans following ingestion of a glass of water (240 mL, as recommended for bioavailability/bioequivalence (BA/BE) studies), using recently validated noninvasive magnetic resonance imaging (MRI) methods. Twelve healthy volunteers underwent upper and lower abdominal MRI scans before drinking 240 mL (8 fluid ounces) of water. After ingesting the water, they were scanned at intervals for 2 h. The drink volume, inclusion criteria, and fasting conditions matched the international standards for BA/BE testing in healthy volunteers. The images were processed for gastric and intestinal total water volumes and for the number and volume of separate intestinal water pockets larger than 0.5 mL. The fasted stomach contained 35 ± 7 mL (mean ± SEM) of resting water. Upon drinking, the gastric fluid rose to 242 ± 9 mL. The gastric water volume declined rapidly after that with a half emptying time (T50%) of 13 ± 1 min. The mean gastric volume returned back to baseline 45 min after the drink. The fasted small bowel contained a total volume of 43 ± 14 mL of resting water. Twelve minutes after ingestion of water, small bowel water content rose to a maximum value of 94 ± 24 mL contained within 15 ± 2 pockets of 6 ± 2 mL each. At 45 min, when the glass of water had emptied completely from the stomach, total intestinal water volume was 77 ± 15 mL distributed into 16 ± 3 pockets of 5 ± 1 mL each. MRI provided unprecedented insights into

  10. [Clinical target volume delineation for radiotherapy of the esophagus].

    PubMed

    Lazarescu, I; Thureau, S; Nkhali, L; Pradier, O; Dubray, B

    2013-10-01

    The dense lymphatic network of the esophagus facilitates tumour spreading along the cephalo-caudal axis and to locoregional lymph nodes. A better understanding of microscopic invasion by tumour cells, based on histological analysis of surgical specimens and analysis of recurrence sites, has justified a reduction in radiotherapy target volumes. The delineation of the clinical target volume (CTV) depends on tumour characteristics (site, histology) and on its spread as assessed on endoscopic ultrasonography and ((18)F)-fluorodeoxyglucose positron-emission tomography (FDG-PET). We propose that positive and negative predictive values for FDG-PET should be used to adapt the CTV according to the risk of nodal involvement. Copyright © 2013 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  11. International Spine Radiosurgery Consortium Consensus Guidelines for Target Volume Definition in Spinal Stereotactic Radiosurgery

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cox, Brett W., E-mail: coxb@mskcc.org; Spratt, Daniel E.; Lovelock, Michael

    2012-08-01

    Purpose: Spinal stereotactic radiosurgery (SRS) is increasingly used to manage spinal metastases. However, target volume definition varies considerably and no consensus target volume guidelines exist. This study proposes consensus target volume definitions using common scenarios in metastatic spine radiosurgery. Methods and Materials: Seven radiation oncologists and 3 neurological surgeons with spinal radiosurgery expertise independently contoured target and critical normal structures for 10 cases representing common scenarios in metastatic spine radiosurgery. Each set of volumes was imported into the Computational Environment for Radiotherapy Research. Quantitative analysis was performed using an expectation maximization algorithm for Simultaneous Truth and Performance Level Estimation (STAPLE)more » with kappa statistics calculating agreement between physicians. Optimized confidence level consensus contours were identified using histogram agreement analysis and characterized to create target volume definition guidelines. Results: Mean STAPLE agreement sensitivity and specificity was 0.76 (range, 0.67-0.84) and 0.97 (range, 0.94-0.99), respectively, for gross tumor volume (GTV) and 0.79 (range, 0.66-0.91) and 0.96 (range, 0.92-0.98), respectively, for clinical target volume (CTV). Mean kappa agreement was 0.65 (range, 0.54-0.79) for GTV and 0.64 (range, 0.54-0.82) for CTV (P<.01 for GTV and CTV in all cases). STAPLE histogram agreement analysis identified optimal consensus contours (80% confidence limit). Consensus recommendations include that the CTV should include abnormal marrow signal suspicious for microscopic invasion and an adjacent normal bony expansion to account for subclinical tumor spread in the marrow space. No epidural CTV expansion is recommended without epidural disease, and circumferential CTVs encircling the cord should be used only when the vertebral body, bilateral pedicles/lamina, and spinous process are all involved or there is extensive

  12. An inexpensive and fast method for infiltration coating of complex geometry matrices for ISOL production target applications

    NASA Astrophysics Data System (ADS)

    Kawai, Y.; Alton, G. D.; Bilheux, J.-C.

    2005-12-01

    An inexpensive, fast, and close to universal infiltration coating technique has been developed for fabricating fast diffusion-release ISOL targets. Targets are fabricated by deposition of finely divided (∼1 μm) compound materials in a paint-slurry onto highly permeable, complex structure reticulated-vitreous-carbon-foam (RVCF) matrices, followed by thermal heat treatment. In this article, we describe the coating method and present information on the physical integrity, uniformity of deposition, and matrix adherence of SiC, HfC and UC2 targets, destined for on-line use as targets at the Holifield Radioactive Ion Beam Facility (HRIBF).

  13. Method and apparatus for producing cryogenic targets

    DOEpatents

    Murphy, James T.; Miller, John R.

    1984-01-01

    An improved method and apparatus are given for producing cryogenic inertially driven fusion targets in the fast isothermal freezing (FIF) method. Improved coupling efficiency and greater availability of volume near the target for diagnostic purposes and for fusion driver beam propagation result. Other embodiments include a new electrical switch and a new explosive detonator, all embodiments making use of a purposeful heating by means of optical fibers.

  14. Isochoric heating and strong blast wave formation driven by fast electrons in solid-density targets

    NASA Astrophysics Data System (ADS)

    Santos, J. J.; Vauzour, B.; Touati, M.; Gremillet, L.; Feugeas, J.-L.; Ceccotti, T.; Bouillaud, R.; Deneuville, F.; Floquet, V.; Fourment, C.; Hadj-Bachir, M.; Hulin, S.; Morace, A.; Nicolaï, Ph; d'Oliveira, P.; Reau, F.; Samaké, A.; Tcherbakoff, O.; Tikhonchuk, V. T.; Veltcheva, M.; Batani, D.

    2017-10-01

    We experimentally investigate the fast (< 1 {ps}) isochoric heating of multi-layer metallic foils and subsequent high-pressure hydrodynamics induced by energetic electrons driven by high-intensity, high-contrast laser pulses. The early-time temperature profile inside the target is measured from the streaked optical pyrometry of the target rear side. This is further characterized from benchmarked simulations of the laser-target interaction and the fast electron transport. Despite a modest laser energy (< 1 {{J}}), the early-time high pressures and associated gradients launch inwards a strong compression wave developing over ≳ 10 ps into a ≈ 140 {Mbar} blast wave, according to hydrodynamic simulations, consistent with our measurements. These experimental and numerical findings pave the way to a short-pulse-laser-based platform dedicated to high-energy-density physics studies.

  15. A fast recognition method of warhead target in boost phase using kinematic features

    NASA Astrophysics Data System (ADS)

    Chen, Jian; Xu, Shiyou; Tian, Biao; Wu, Jianhua; Chen, Zengping

    2015-12-01

    The radar targets number increases from one to more when the ballistic missile is in the process of separating the lower stage rocket or casting covers or other components. It is vital to identify the warhead target quickly among these multiple targets for radar tracking. A fast recognition method of the warhead target is proposed to solve this problem by using kinematic features, utilizing fuzzy comprehensive method and information fusion method. In order to weaken the influence of radar measurement noise, an extended Kalman filter with constant jerk model (CJEKF) is applied to obtain more accurate target's motion information. The simulation shows the validity of the algorithm and the effects of the radar measurement precision upon the algorithm's performance.

  16. Method and apparatus for producing cryogenic targets

    DOEpatents

    Murphy, J.T.; Miller, J.R.

    1984-08-07

    An improved method and apparatus are given for producing cryogenic inertially driven fusion targets in the fast isothermal freezing (FIF) method. Improved coupling efficiency and greater availability of volume near the target for diagnostic purposes and for fusion driver beam propagation result. Other embodiments include a new electrical switch and a new explosive detonator, all embodiments making use of a purposeful heating by means of optical fibers. 6 figs.

  17. Postoperative radiation in esophageal squamous cell carcinoma and target volume delineation

    PubMed Central

    Zhu, Yingming; Li, Minghuan; Kong, Li; Yu, Jinming

    2016-01-01

    Esophageal cancer is the sixth leading cause of cancer death worldwide, and patients who are treated with surgery alone, without neoadjuvant therapies, experience frequent relapses. Whether postoperative therapies could reduce the recurrence or improve overall survival is still controversial for these patients. The purpose of our review is to figure out the value of postoperative adjuvant therapy and address the disputes about target volume delineation according to published data. Based on the evidence of increased morbidity and disadvantages on patient survival caused by postoperative chemotherapy or radiotherapy (RT) alone provided by studies in the early 1990s, the use of postoperative adjuvant therapies in cases of esophageal squamous cell carcinoma has diminished substantially and has been replaced gradually by neoadjuvant chemoradiation. With advances in surgery and RT, accumulating evidence has recently rekindled interest in the delivery of postoperative RT or chemoradiotherapy in patients with stage T3/T4 or N1 (lymph node positive) carcinomas after radical surgery. However, due to complications with the standard radiation field, a nonconforming modified field has been adopted in most studies. Therefore, we analyze different field applications and provide suggestions on the optimization of the radiation field based on the major sites of relapse and the surgical non-clearance area. For upper and middle thoracic esophageal carcinomas, the bilateral supraclavicular and superior mediastinal areas remain common sites of recurrence and should be encompassed within the clinical target volume. In contrast, a consensus has yet to be reached regarding lower thoracic esophageal carcinomas; the “standard” clinical target volume is still recommended. Further studies of larger sample sizes should focus on different recurrence patterns, categorized by tumor locations, refined classifications, and differing molecular biology, to provide more information on the

  18. Guiding and focusing of fast electron beams produced by ultra-intense laser pulse using a double cone funnel target

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Wen-shuai; Cai, Hong-bo, E-mail: Cai-hongbo@iapcm.ac.cn; HEDPS, Center for Applied Physics and Technology, Peking University, Beijing 100871

    A novel double cone funnel target design aiming at efficiently guiding and focusing fast electron beams produced in high intensity (>10{sup 19 }W/cm{sup 2}) laser-solid interactions is investigated via two-dimensional particle-in-cell simulations. The forward-going fast electron beams are shown to be directed and focused to a smaller size in comparison with the incident laser spot size. This plasma funnel attached on the cone target guides and focuses electrons in a manner akin to the control of liquid by a plastic funnel. Such device has the potential to add substantial design flexibility and prevent inefficiencies for important applications such as fast ignition.more » Two reasons account for the collimation of fast electron beams. First, the sheath electric fields and quasistatic magnetic fields inside the vacuum gap of the double cone provide confinement of the fast electrons in the laser-plasma interaction region. Second, the interface magnetic fields inside the beam collimator further guide and focus the fast electrons during the transport. The application of this technique to cone-guided fast ignition is considered, and it is shown that it can enhance the laser energy deposition in the compressed fuel plasma by a factor of 2 in comparison with the single cone target case.« less

  19. Calculation of Lung Cancer Volume of Target Based on Thorax Computed Tomography Images using Active Contour Segmentation Method for Treatment Planning System

    NASA Astrophysics Data System (ADS)

    Patra Yosandha, Fiet; Adi, Kusworo; Edi Widodo, Catur

    2017-06-01

    In this research, calculation process of the lung cancer volume of target based on computed tomography (CT) thorax images was done. Volume of the target calculation was done in purpose to treatment planning system in radiotherapy. The calculation of the target volume consists of gross tumor volume (GTV), clinical target volume (CTV), planning target volume (PTV) and organs at risk (OAR). The calculation of the target volume was done by adding the target area on each slices and then multiply the result with the slice thickness. Calculations of area using of digital image processing techniques with active contour segmentation method. This segmentation for contouring to obtain the target volume. The calculation of volume produced on each of the targets is 577.2 cm3 for GTV, 769.9 cm3 for CTV, 877.8 cm3 for PTV, 618.7 cm3 for OAR 1, 1,162 cm3 for OAR 2 right, and 1,597 cm3 for OAR 2 left. These values indicate that the image processing techniques developed can be implemented to calculate the lung cancer target volume based on CT thorax images. This research expected to help doctors and medical physicists in determining and contouring the target volume quickly and precisely.

  20. A long-lived tritiated titanium target for fast neutron production

    NASA Astrophysics Data System (ADS)

    Hughey, B. J.

    1995-03-01

    Diagnostic techniques using neutron beams have a broad spectrum of applications in advanced manufacturing, explosives and contraband detection, medicine, and industry. The most suitable nuclear reaction for producing large fluxes of fast neutrons at low bombarding energy is the H(d,n)-3 He-4, i.e. d-T, reaction. The lifetime of currently used d-T neutron generators is limited by the gradual evolution of tritium gas from the target during bombardment. This paper is a report of work in progress to develop a method for inhibiting the replacement of tritium with beam deuterons and thus preventing the evolution of tritium gas leading to reduced neutron yield. It is anticipated that tritiated target lifetime can be increased by at least an order of magnitude by using a range-thin tritiated titanium target mounted on a substrate with a high hydrogen diffusivity, such as niobium. Lifetime can be further enhanced by increasing the deuteron beam bombarding energy from the typical value of 200 keV to 600 keV. The results of experiments demonstrating the effect of hydrogen diffusion coefficient on concentration of implanted beam deuterons in candidate substrate materials (Cu, Pd, and Nb) are presented, and issues relevant to the fabrication of a tritiated titanium target on a niobium substrate are discussed.

  1. Magnetic Resonance Imaging Quantification of Fasted State Colonic Liquid Pockets in Healthy Humans.

    PubMed

    Murray, Kathryn; Hoad, Caroline L; Mudie, Deanna M; Wright, Jeff; Heissam, Khaled; Abrehart, Nichola; Pritchard, Susan E; Al Atwah, Salem; Gowland, Penny A; Garnett, Martin C; Amidon, Gregory E; Spiller, Robin C; Amidon, Gordon L; Marciani, Luca

    2017-08-07

    The rate and extent of drug dissolution and absorption from solid oral dosage forms is highly dependent on the volume of liquid in the gastrointestinal tract (GIT). However, little is known about the time course of GIT liquid volumes after drinking a glass of water (8 oz), particularly in the colon, which is a targeted site for both locally and systemically acting drug products. Previous magnetic resonance imaging (MRI) studies offered novel insights on GIT liquid distribution in fasted humans in the stomach and small intestine, and showed that freely mobile liquid in the intestine collects in fairly distinct regions or "pockets". Based on this previous pilot data, we hypothesized that (1) it is possible to quantify the time course of the volume and number of liquid pockets in the undisturbed colon of fasted healthy humans following ingestion of 240 mL, using noninvasive MRI methods; (2) the amount of freely mobile water in the fasted human colon is of the order of only a few milliliters. Twelve healthy volunteers fasted overnight and underwent fasted abdominal MRI scans before drinking 240 mL (∼8 fluid ounces) of water. After ingesting the water they were scanned at frequent intervals for 2 h. The images were processed to quantify freely mobile water in the total and regional colon: ascending, transverse, and descending. The fasted colon contained (mean ± SEM) 11 ± 5 pockets of resting liquid with a total volume of 2 ± 1 mL (average). The colonic fluid peaked at 7 ± 4 mL 30 min after the water drink. This peak fluid was distributed in 17 ± 7 separate liquid pockets in the colon. The regional analysis showed that pockets of free fluid were found primarily in the ascending colon. The interindividual variability was very high; the subjects showed a range of number of colonic fluid pockets from 0 to 89 and total colonic freely mobile fluid volume from 0 to 49 mL. This is the first study measuring the time course of the number, regional location, and volume of

  2. NOTE: Wobbled splatting—a fast perspective volume rendering method for simulation of x-ray images from CT

    NASA Astrophysics Data System (ADS)

    Birkfellner, Wolfgang; Seemann, Rudolf; Figl, Michael; Hummel, Johann; Ede, Christopher; Homolka, Peter; Yang, Xinhui; Niederer, Peter; Bergmann, Helmar

    2005-05-01

    3D/2D registration, the automatic assignment of a global rigid-body transformation matching the coordinate systems of patient and preoperative volume scan using projection images, is an important topic in image-guided therapy and radiation oncology. A crucial part of most 3D/2D registration algorithms is the fast computation of digitally rendered radiographs (DRRs) to be compared iteratively to radiographs or portal images. Since registration is an iterative process, fast generation of DRRs—which are perspective summed voxel renderings—is desired. In this note, we present a simple and rapid method for generation of DRRs based on splat rendering. As opposed to conventional splatting, antialiasing of the resulting images is not achieved by means of computing a discrete point spread function (a so-called footprint), but by stochastic distortion of either the voxel positions in the volume scan or by the simulation of a focal spot of the x-ray tube with non-zero diameter. Our method generates slightly blurred DRRs suitable for registration purposes at framerates of approximately 10 Hz when rendering volume images with a size of 30 MB.

  3. Drinking 300 mL of clear fluid two hours before surgery has no effect on gastric fluid volume and pH in fasting and non-fasting obese patients.

    PubMed

    Maltby, J Roger; Pytka, Saul; Watson, Neil C; Cowan, Robert A McTaggart; Fick, Gordon H

    2004-02-01

    To determine whether, in obese [body mass index (BMI) > 30 kg.m(2)] patients, oral intake of 300 mL clear liquid two hours before elective surgery affects the volume and pH of gastric contents at induction of anesthesia. A single-blind, randomized study of 126 adult patients, age > or = 18 yr, ASA physical status I or II, BMI > 30 kg.m(2) who were scheduled for elective surgery under general anesthesia. Patients were excluded if they had diabetes mellitus, symptoms of gastroesophageal reflux, or had taken medication within 24 hr that affects gastric secretion, gastric fluid pH or gastric emptying. All patients fasted from midnight and were randomly assigned to fasting or fluid group. Two hours before their scheduled time of surgery, all patients drank 10 mL of water containing phenol red 50 mg. Those in the fluid group followed with 300 mL clear liquid of their choice. Immediately following induction of general anesthesia and tracheal intubation, gastric contents were aspirated through a multiorifice Salem sump tube. The fluid volume, pH and phenol red concentration were recorded. Median (range) values in fasting vs fluid groups were: gastric fluid volume 26 (3-107) mL vs 30 (3-187) mL, pH 1.78 (1.31-7.08) vs 1.77 (1.27-7.34) and phenol red retrieval 0.1 (0-30)% vs 0.2 (0-15)%. Differences between groups were not statistically significant. Obese patients without comorbid conditions should follow the same fasting guidelines as non-obese patients and be allowed to drink clear liquid until two hours before elective surgery, inasmuch as obesity per se is not considered a risk factor for pulmonary aspiration.

  4. Results of thermal test of metallic molybdenum disk target and fast-acting valve testing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Virgo, M.; Chemerisov, S.; Gromov, R.

    2016-12-01

    This report describes the irradiation conditions for thermal testing of helium-cooled metallic disk targets that was conducted on March 9, 2016, at the Argonne National Laboratory electron linac. The four disks in this irradiation were pressed and sintered by Oak Ridge National Laboratory from molybdenum metal powder. Two of those disks were instrumented with thermocouples. Also reported are results of testing a fast-acting-valve system, which was designed to protect the accelerator in case of a target-window failure.

  5. Implosion and heating experiments of fast ignition targets by Gekko-XII and LFEX lasers

    NASA Astrophysics Data System (ADS)

    Shiraga, H.; Fujioka, S.; Nakai, M.; Watari, T.; Nakamura, H.; Arikawa, Y.; Hosoda, H.; Nagai, T.; Koga, M.; Kikuchi, H.; Ishii, Y.; Sogo, T.; Shigemori, K.; Nishimura, H.; Zhang, Z.; Tanabe, M.; Ohira, S.; Fujii, Y.; Namimoto, T.; Sakawa, Y.; Maegawa, O.; Ozaki, T.; Tanaka, K. A.; Habara, H.; Iwawaki, T.; Shimada, K.; Key, M.; Norreys, P.; Pasley, J.; Nagatomo, H.; Johzaki, T.; Sunahara, A.; Murakami, M.; Sakagami, H.; Taguchi, T.; Norimatsu, T.; Homma, H.; Fujimoto, Y.; Iwamoto, A.; Miyanaga, N.; Kawanaka, J.; Kanabe, T.; Jitsuno, T.; Nakata, Y.; Tsubakimoto, K.; Sueda, K.; Kodama, R.; Kondo, K.; Morio, N.; Matsuo, S.; Kawasaki, T.; Sawai, K.; Tsuji, K.; Murakami, H.; Sarukura, N.; Shimizu, T.; Mima, K.; Azechi, H.

    2013-11-01

    The FIREX-1 project, the goal of which is to demonstrate fuel heating up to 5 keV by fast ignition scheme, has been carried out since 2003 including construction and tuning of LFEX laser and integrated experiments. Implosion and heating experiment of Fast Ignition targets have been performed since 2009 with Gekko-XII and LFEX lasers. A deuterated polystyrene shell target was imploded with the 0.53- μm Gekko-XII, and the 1.053- μm beam of the LFEX laser was injected through a gold cone attached to the shell to generate hot electrons to heat the imploded fuel plasma. Pulse contrast ratio of the LFEX beam was significantly improved. Also a variety of plasma diagnostic instruments were developed to be compatible with harsh environment of intense hard x-rays (γ rays) and electromagnetic pulses due to the intense LFEX beam on the target. Large background signals around the DD neutron signal in time-of-flight record of neutron detector were found to consist of neutrons via (γ,n) reactions and scattered gamma rays. Enhanced neutron yield was confirmed by carefully eliminating such backgrounds. Neutron enhancement up to 3.5 × 107 was observed. Heating efficiency was estimated to be 10-20% assuming a uniform temperature rise model.

  6. Physiological and biochemical principles underlying volume-targeted therapy--the "Lund concept".

    PubMed

    Nordström, Carl-Henrik

    2005-01-01

    The optimal therapy of sustained increase in intracranial pressure (ICP) remains controversial. The volume-targeted therapy ("Lund concept") discussed in this article focuses on the physiological volume regulation of the intracranial compartments. The balance between effective transcapillary hydrostatic and osmotic pressures constitutes the driving force for transcapillary fluid exchange. The low permeability for sodium and chloride combined with the high crystalloid osmotic pressure (approximately 5700 mmHg) on both sides of the blood-brain barrier (BBB) counteracts fluid exchange across the intact BBB. Additionally, variations in systemic blood pressure generally are not transmitted to these capillaries because cerebral intracapillary hydrostatic pressure (and blood flow) is physio-logically tightly autoregulated. Under pathophysiological conditions, the BBB may be partially disrupted. Transcapillary water exchange is then determined by the differences in hydrostatic and colloid osmotic pressure between the intra- and extracapillary compartments. Pressure autoregulation of cerebral blood flow is likely to be impaired in these conditions. A high cerebral perfusion pressure accordingly increases intracapillary hydrostatic pressure and leads to increased intracerebral water content and an increase in ICP. The volume-targeted "Lund concept" has been evaluated in experimental and clinical studies to examine the physiological and biochemical (utilizing intracerebral microdialysis) effects, and the clinical experiences have been favorable.

  7. Pre- and postoperative radiotherapy for extremity soft tissue sarcoma: Evaluation of inter-observer target volume contouring variability among French sarcoma group radiation oncologists.

    PubMed

    Sargos, P; Charleux, T; Haas, R L; Michot, A; Llacer, C; Moureau-Zabotto, L; Vogin, G; Le Péchoux, C; Verry, C; Ducassou, A; Delannes, M; Mervoyer, A; Wiazzane, N; Thariat, J; Sunyach, M P; Benchalal, M; Laredo, J D; Kind, M; Gillon, P; Kantor, G

    2018-04-01

    The purpose of this study was to evaluate, during a national workshop, the inter-observer variability in target volume delineation for primary extremity soft tissue sarcoma radiation therapy. Six expert sarcoma radiation oncologists (members of French Sarcoma Group) received two extremity soft tissue sarcoma radiation therapy cases 1: one preoperative and one postoperative. They were distributed with instructions for contouring gross tumour volume or reconstructed gross tumour volume, clinical target volume and to propose a planning target volume. The preoperative radiation therapy case was a patient with a grade 1 extraskeletal myxoid chondrosarcoma of the thigh. The postoperative case was a patient with a grade 3 pleomorphic undifferentiated sarcoma of the thigh. Contour agreement analysis was performed using kappa statistics. For the preoperative case, contouring agreement regarding GTV, gross tumour volume GTV, clinical target volume and planning target volume were substantial (kappa between 0.68 and 0.77). In the postoperative case, the agreement was only fair for reconstructed gross tumour volume (kappa: 0.38) but moderate for clinical target volume and planning target volume (kappa: 0.42). During the workshop discussion, consensus was reached on most of the contour divergences especially clinical target volume longitudinal extension. The determination of a limited cutaneous cover was also discussed. Accurate delineation of target volume appears to be a crucial element to ensure multicenter clinical trial quality assessment, reproducibility and homogeneity in delivering RT. radiation therapy RT. Quality assessment process should be proposed in this setting. We have shown in our study that preoperative radiation therapy of extremity soft tissue sarcoma has less inter-observer contouring variability. Copyright © 2018 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  8. A novel concept for tumour targeting with radiation: Inverse dose-painting or targeting the "Low Drug Uptake Volume".

    PubMed

    Yaromina, Ala; Granzier, Marlies; Biemans, Rianne; Lieuwes, Natasja; van Elmpt, Wouter; Shakirin, Georgy; Dubois, Ludwig; Lambin, Philippe

    2017-09-01

    We tested a novel treatment approach combining (1) targeting radioresistant hypoxic tumour cells with the hypoxia-activated prodrug TH-302 and (2) inverse radiation dose-painting to boost selectively non-hypoxic tumour sub-volumes having no/low drug uptake. 18 F-HX4 hypoxia tracer uptake measured with a clinical PET/CT scanner was used as a surrogate of TH-302 activity in rhabdomyosarcomas growing in immunocompetent rats. Low or high drug uptake volume (LDUV/HDUV) was defined as 40% of the GTV with the lowest or highest 18 F-HX4 uptake, respectively. Two hours post TH-302/saline administration, animals received either single dose radiotherapy (RT) uniformly (15 or 18.5Gy) or a dose-painted non-uniform radiation (15Gy) with 50% higher dose to LDUV or HDUV (18.5Gy). Treatment plans were created using Eclipse treatment planning system and radiation was delivered using VMAT. Tumour response was quantified as time to reach 3 times starting tumour volume. Non-uniform RT boosting tumour sub-volume with low TH-302 uptake (LDUV) was superior to the same dose escalation to HDUV (p<0.0001) and uniform RT with the same mean dose 15Gy (p=0.0077). Noteworthy, dose escalation to LDUV required on average 3.5Gy lower dose to the GTV to achieve similar tumour response as uniform dose escalation. The results support targeted dose escalation to non-hypoxic tumour sub-volume with no/low activity of hypoxia-activated prodrugs. This strategy applies on average a lower radiation dose and is as effective as uniform dose escalation to the entire tumour. It could be applied to other type of drugs provided that their distribution can be imaged. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  9. Changes in gene expression in PBMCs profiles of PPARα target genes in obese and non-obese individuals during fasting.

    PubMed

    Felicidade, Ingrid; Marcarini, Juliana Cristina; Carreira, Clísia Mara; Amarante, Marla Karine; Afman, Lydia A; Mantovani, Mário Sérgio; Ribeiro, Lúcia Regina

    2015-01-01

    The prevalence of obesity has risen dramatically and the World Health Organization estimates that 700 million people will be obese worldwide by 2015. Approximately, 50% of the Brazilian population above 20 years of age is overweight, and 16% is obese. This study aimed to evaluate the differences in the expression of PPARα target genes in human peripheral blood mononuclear cells (PBMCs) and free fatty acids (FFA) in obese and non-obese individuals after 24 h of fasting. We first presented evidence that Brazilian people exhibit expression changes in PPARα target genes in PBMCs under fasting conditions. Q-PCR was utilized to assess the mRNA expression levels of target genes. In both groups, the FFA concentrations increased significantly after 24 h of fasting. The basal FFA mean concentration was two-fold higher in the obese group compared with the non-obese group. After fasting, all genes evaluated in this study showed increased expression levels compared with basal expression in both groups. However, our results reveal no differences in gene expression between the obese and non-obese, more studies are necessary to precisely delineate the associated mechanisms, particularly those that include groups with different degrees of obesity and patients with diabetes mellitus type 2 because the expression of the main genes that are involved in β-oxidation and glucose level maintenance are affected by these factors. © 2014 S. Karger AG, Basel.

  10. Optimal and fast rotational alignment of volumes with missing data in Fourier space.

    PubMed

    Shatsky, Maxim; Arbelaez, Pablo; Glaeser, Robert M; Brenner, Steven E

    2013-11-01

    Electron tomography of intact cells has the potential to reveal the entire cellular content at a resolution corresponding to individual macromolecular complexes. Characterization of macromolecular complexes in tomograms is nevertheless an extremely challenging task due to the high level of noise, and due to the limited tilt angle that results in missing data in Fourier space. By identifying particles of the same type and averaging their 3D volumes, it is possible to obtain a structure at a more useful resolution for biological interpretation. Currently, classification and averaging of sub-tomograms is limited by the speed of computational methods that optimize alignment between two sub-tomographic volumes. The alignment optimization is hampered by the fact that the missing data in Fourier space has to be taken into account during the rotational search. A similar problem appears in single particle electron microscopy where the random conical tilt procedure may require averaging of volumes with a missing cone in Fourier space. We present a fast implementation of a method guaranteed to find an optimal rotational alignment that maximizes the constrained cross-correlation function (cCCF) computed over the actual overlap of data in Fourier space. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Laser Irradiated Foam Targets: Absorption and Radiative Properties

    NASA Astrophysics Data System (ADS)

    Salvadori, Martina; Luigi Andreoli, Pier; Cipriani, Mattia; Consoli, Fabrizio; Cristofari, Giuseppe; De Angelis, Riccardo; di Giorgio, Giorgio; Giulietti, Danilo; Ingenito, Francesco; Gus'kov, Sergey Yu.; Rupasov, Alexander A.

    2018-01-01

    An experimental campaign to characterize the laser radiation absorption of foam targets and the subsequent emission of radiation from the produced plasma was carried out in the ABC facility of the ENEA Research Center in Frascati (Rome). Different targets have been used: plastic in solid or foam state and aluminum targets. The activated different diagnostics allowed to evaluate the plasma temperature, the density distribution, the fast particle spectrum and the yield of the X-Ray radiation emitted by the plasma for the different targets. These results confirm the foam homogenization action on laser-plasma interaction, mainly attributable to the volume absorption of the laser radiation propagating in such structured materials. These results were compared with simulation absorption models of the laser propagating into a foam target.

  12. Advanced plastic scintillators for fast neutron discrimination

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feng, Patrick L; Anstey, Mitchell; Doty, F. Patrick

    2014-09-01

    The present work addresses the need for solid-state, fast neutron discriminating scintillators that possess higher light yields and faster decay kinetics than existing organic scintillators. These respective attributes are of critical importance for improving the gamma-rejection capabilities and increasing the neutron discrimination performance under high-rate conditions. Two key applications that will benefit from these improvements include large-volume passive detection scenarios as well as active interrogation search for special nuclear materials. Molecular design principles were employed throughout this work, resulting in synthetically tailored materials that possess the targeted scintillation properties.

  13. Target volume motion during anal cancer image guided radiotherapy using cone-beam computed tomography.

    PubMed

    Brooks, Corrinne J; Bernier, Laurence; Hansen, Vibeke N; Tait, Diana M

    2018-05-01

    Literature regarding image-guidance and interfractional motion of the anal canal (AC) during anal cancer radiotherapy is sparse. This study investigates interfractional AC motion during anal cancer radiotherapy. Bone matched cone beam CT (CBCT) images were acquired for 20 patients receiving anal cancer radiotherapy allowing population systematic and random error calculations. 12 were selected to investigate interfractional AC motion. Primary anal gross tumour volume and clinical target volume (CTVa) were contoured on each CBCT. CBCT CTVa volumes were compared to planning CTVa. CBCT CTVa volumes were combined into a CBCT-CTVa envelope for each patient. Maximum distortion between each orthogonal border of the planning CTVa and CBCT-CTVa envelope was measured. Frequency, volume and location of CBCT-CTVa envelope beyond the planning target volume (PTVa) was analysed. Population systematic and random errors were 1 and 3 mm respectively. 112 CBCTs were analysed in the interfractional motion study. CTVa varied between each imaging session particularly T location patients of anorectal origin. CTVa border expansions ≥ 1 cm were seen inferiorly, anteriorly, posteriorly and left direction. The CBCT-CTVa envelope fell beyond the PTVa ≥ 50% imaging sessions (n = 5). Of these CBCT CTVa distortions beyond PTVa, 44% and 32% were in the upper and lower thirds of PTVa respectively. The AC is susceptible to volume changes and shape deformations. Care must be taken when calculating or considering reducing the PTV margin to the anus. Advances in knowledge: Within a limited field of research, this study provides further knowledge of how the AC deforms during anal cancer radiotherapy.

  14. Intensity-Modulated Radiotherapy for Craniospinal Irradiation: Target Volume Considerations, Dose Constraints, and Competing Risks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parker, William; Filion, Edith; Roberge, David

    2007-09-01

    Purpose: To report the results of an analysis of dose received to tissues and organs outside the target volume, in the setting of spinal axis irradiation for the treatment of medulloblastoma, using three treatment techniques. Methods and Materials: Treatment plans (total dose, 23.4 Gy) for a standard two-dimensional (2D) technique, a three-dimensional (3D) technique using a 3D imaging-based target volume, and an intensity-modulated radiotherapy (IMRT) technique, were compared for 3 patients in terms of dose-volume statistics for target coverage, as well as organ at risk (OAR) and overall tissue sparing. Results: Planning target volume coverage and dose homogeneity was superiormore » for the IMRT plans for V{sub 95%} (IMRT, 100%; 3D, 96%; 2D, 98%) and V{sub 107%} (IMRT, 3%; 3D, 38%; 2D, 37%). In terms of OAR sparing, the IMRT plan was better for all organs and whole-body contour when comparing V{sub 10Gy}, V{sub 15Gy}, and V{sub 20Gy}. The 3D plan was superior for V{sub 5Gy} and below. For the heart and liver in particular, the IMRT plans provided considerable sparing in terms of V{sub 10Gy} and above. In terms of the integral dose, the IMRT plans were superior for liver (IMRT, 21.9 J; 3D, 28.6 J; 2D, 38.6 J) and heart (IMRT, 9 J; 3D, 14.1J; 2D, 19.4 J), the 3D plan for the body contour (IMRT, 349 J; 3D, 337 J; 2D, 555 J). Conclusions: Intensity-modulated radiotherapy is a valid treatment option for spinal axis irradiation. We have shown that IMRT results in sparing of organs at risk without a significant increase in integral dose.« less

  15. Water-filled balloon in the postoperative resection cavity improves dose distribution to target volumes in radiotherapy of maxillary sinus carcinoma.

    PubMed

    Zhang, Qun; Lin, Shi-Rong; He, Fang; Kang, De-Hua; Chen, Guo-Zhang; Luo, Wei

    2011-11-01

    Postoperative radiotherapy is a major treatment for patients with maxillary sinus carcinoma. However, the irregular resection cavity poses a technical difficulty for this treatment, causing uneven dose distribution to target volumes. In this study, we evaluated the dose distribution to target volumes and normal tissues in postoperative intensity-modulated radiotherapy (IMRT) after placing a water-filled balloon into the resection cavity. Three postoperative patients with advanced maxillary sinus carcinoma were selected in this trial. Water-filled balloons and supporting dental stents were fabricated according to the size of the maxillary resection cavity. Simulation CT scans were performed with or without water-filled balloons, IMRT treatment plans were established, and dose distribution to target volumes and organs at risk were evaluated. Compared to those in the treatment plan without balloons, the dose (D98) delivered to 98% of the gross tumor volume (GTV) increased by 2.1 Gy (P = 0.009), homogeneity index (HI) improved by 2.3% (P = 0.001), and target volume conformity index (TCI) of 68 Gy increased by 18.5% (P = 0.011) in the plan with balloons. Dosimetry endpoints of normal tissues around target regions in both plans were not significantly different (P > 0.05) except for the optic chiasm. In the plan without balloons, 68 Gy high-dose regions did not entirely cover target volumes in the ethmoid sinus, posteromedial wall of the maxillary sinus, or surgical margin of the hard palate. In contrast, 68 Gy high-dose regions entirely covered the GTV in the plan with balloons. These results suggest that placing a water-filled balloon in the resection cavity for postoperative IMRT of maxillary sinus carcinoma can reduce low-dose regions and markedly and simultaneously increase dose homogeneity and conformity of target volumes.

  16. The MROI fast tip-tilt correction and target acquisition system

    NASA Astrophysics Data System (ADS)

    Young, John; Buscher, David; Fisher, Martin; Haniff, Christopher; Rea, Alexander; Seneta, Eugene B.; Sun, Xiaowei; Wilson, Donald; Farris, Allen; Olivares, Andres; Selina, Robert

    2012-07-01

    The fast tip-tilt correction system for the Magdalena Ridge Observatory Interferometer (MROI) is being designed and fabricated by the University of Cambridge. The design of the system is currently at an advanced stage and the performance of its critical subsystems has been verified in the laboratory. The system has been designed to meet a demanding set of specifications including satisfying all performance requirements in ambient temperatures down to -5 °C, maintaining the stability of the tip-tilt fiducial over a 5 °C temperature change without recourse to an optical reference, and a target acquisition mode with a 60” field-of-view. We describe the important technical features of the system, which uses an Andor electron-multiplying CCD camera protected by a thermal enclosure, a transmissive optical system with mounts incorporating passive thermal compensation, and custom control software running under Xenomai real-time Linux. We also report results from laboratory tests that demonstrate (a) the high stability of the custom optic mounts and (b) the low readout and compute latencies that will allow us to achieve a 40 Hz closed-loop bandwidth on bright targets.

  17. Radiotherapy planning: PET/CT scanner performances in the definition of gross tumour volume and clinical target volume.

    PubMed

    Brianzoni, Ernesto; Rossi, Gloria; Ancidei, Sergio; Berbellini, Alfonso; Capoccetti, Francesca; Cidda, Carla; D'Avenia, Paola; Fattori, Sara; Montini, Gian Carlo; Valentini, Gianluca; Proietti, Alfredo; Algranati, Carlo

    2005-12-01

    Positron emission tomography is the most advanced scintigraphic imaging technology and can be employed in the planning of radiation therapy (RT). The aim of this study was to evaluate the possible role of fused images (anatomical CT and functional FDG-PET), acquired with a dedicated PET/CT scanner, in delineating gross tumour volume (GTV) and clinical target volume (CTV) in selected patients and thus in facilitating RT planning. Twenty-eight patients were examined, 24 with lung cancer (17 non-small cell and seven small cell) and four with non-Hodgkin's lymphoma in the head and neck region. All patients underwent a whole-body PET scan after a CT scan. The CT images provided morphological volumetric information, and in a second step, the corresponding PET images were overlaid to define the effective target volume. The images were exported off-line via an internal network to an RT simulator. Three patient were excluded from the study owing to change in the disease stage subsequent to the PET/CT study. Among the remaining 25 patients, PET significantly altered the GTV or CTV in 11 (44%) . In five of these 11 cases there was a reduction in GTV or CTV, while in six there was an increase in GTV or CTV. FDG-PET is a highly sensitive imaging modality that offers better visualisation of local and locoregional tumour extension. This study confirmed that co-registration of CT data and FDG-PET images may lead to significant modifications of RT planning and patient management.

  18. Implications of improved diagnostic imaging of small nodal metastases in head and neck cancer: Radiotherapy target volume transformation and dose de-escalation.

    PubMed

    van den Bosch, Sven; Vogel, Wouter V; Raaijmakers, Cornelis P; Dijkema, Tim; Terhaard, Chris H J; Al-Mamgani, Abrahim; Kaanders, Johannes H A M

    2018-05-03

    Diagnostic imaging continues to evolve, and now has unprecedented accuracy for detecting small nodal metastasis. This influences the tumor load in elective target volumes and subsequently has consequences for the radiotherapy dose required to control disease in these volumes. Small metastases that used to remain subclinical and were included in elective volumes, will nowadays be detected and included in high-dose volumes. Consequentially, high-dose volumes will more often contain low-volume disease. These target volume transformations lead to changes in the tumor burden in elective and "gross" tumor volumes with implications for the radiotherapy dose prescribed to these volumes. For head and neck tumors, nodal staging has evolved from mere palpation to combinations of high-resolution imaging modalities. A traditional nodal gross tumor volume in the neck typically had a minimum diameter of 10-15 mm, while nowadays much smaller tumor deposits are detected in lymph nodes. However, the current dose levels for elective nodal irradiation were empirically determined in the 1950s, and have not changed since. In this report the radiobiological consequences of target volume transformation caused by modern imaging of the neck are evaluated, and theoretically derived reductions of dose in radiotherapy for head and neck cancer are proposed. The concept of target volume transformation and subsequent strategies for dose adaptation applies to many other tumor types as well. Awareness of this concept may result in new strategies for target definition and selection of dose levels with the aim to provide optimal tumor control with less toxicity. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Analysis of FET-PET imaging for target volume definition in patients with gliomas treated with conformal radiotherapy.

    PubMed

    Rieken, Stefan; Habermehl, Daniel; Giesel, Frederik L; Hoffmann, Christoph; Burger, Ute; Rief, Harald; Welzel, Thomas; Haberkorn, Uwe; Debus, Jürgen; Combs, Stephanie E

    2013-12-01

    Modern radiotherapy (RT) techniques such as stereotactic RT, intensity-modulated RT, or particle irradiation allow local dose escalation with simultaneous sparing of critical organs. Several trials are currently investigating their benefit in glioma reirradiation and boost irradiation. Target volume definition is of critical importance especially when steep dose gradient techniques are employed. In this manuscript we investigate the impact of O-(2-(F-18)fluoroethyl)-l-tyrosine-positron emission tomography/computer tomography (FET-PET/CT) on target volume definition in low and high grade glioma patients undergoing either first or re-irradiation with particles. We investigated volumetric size and uniformity of magnetic resonance imaging (MRI)- vs. FET-PET/CT-derived gross tumor volumes (GTVs) and planning target volumes (PTVs) of 41 glioma patients. Clinical cases are presented to demonstrate potential benefits of integrating FET-PET/CT-planning into daily routine. Integrating FET-uptake into the delineation of GTVs yields larger volumes. Combined modality-derived PTVs are significantly enlarged in high grade glioma patients and in case of primary RT. The congruence of MRI and FET signals for the identification of glioma GTVs is poor with mean uniformity indices of 0.39. MRI-based PTVs miss 17% of FET-PET/CT-based GTVs. Non significant alterations were detected in low grade glioma patients and in those undergoing reirradiation. Target volume definition for malignant gliomas during initial RT may yield significantly differing results depending upon the imaging modality, which the contouring process is based upon. The integration of both MRI and FET-PET/CT may help to improve GTV coverage by avoiding larger incongruences between physical and biological imaging techniques. In low grade gliomas and in cases of reirradiation, more studies are needed in order to investigate a potential benefit of FET-PET/CT for planning of RT. Copyright © 2013 Elsevier Ireland Ltd. All

  20. Variations of target volume definition and daily target volume localization in stereotactic body radiotherapy for early-stage non–small cell lung cancer patients under abdominal compression

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Han, Chunhui, E-mail: chan@coh.org; Sampath, Sagus; Schultheisss, Timothy E.

    We aimed to compare gross tumor volumes (GTV) in 3-dimensional computed tomography (3DCT) simulation and daily cone beam CT (CBCT) with the internal target volume (ITV) in 4-dimensional CT (4DCT) simulation in stereotactic body radiotherapy (SBRT) treatment of patients with early-stage non–small cell lung cancer (NSCLC) under abdominal compression. We retrospectively selected 10 patients with NSCLC who received image-guided SBRT treatments under abdominal compression with daily CBCT imaging. GTVs were contoured as visible gross tumor on the planning 3DCT and daily CBCT, and ITVs were contoured using maximum intensity projection (MIP) images of the planning 4DCT. Daily CBCTs were registeredmore » with 3DCT and MIP images by matching of bony landmarks in the thoracic region to evaluate interfractional GTV position variations. Relative to MIP-based ITVs, the average 3DCT-based GTV volume was 66.3 ± 17.1% (range: 37.5% to 92.0%) (p < 0.01 in paired t-test), and the average CBCT-based GTV volume was 90.0 ± 6.7% (daily range: 75.7% to 107.1%) (p = 0.02). Based on bony anatomy matching, the center-of-mass coordinates for CBCT-based GTVs had maximum absolute shift of 2.4 mm (left-right), 7.0 mm (anterior-posterior [AP]), and 5.2 mm (superior-inferior [SI]) relative to the MIP-based ITV. CBCT-based GTVs had average overlapping ratio of 81.3 ± 11.2% (range: 45.1% to 98.9%) with the MIP-based ITV, and 57.7 ± 13.7% (range: 35.1% to 83.2%) with the 3DCT-based GTV. Even with abdominal compression, both 3DCT simulations and daily CBCT scans significantly underestimated the full range of tumor motion. In daily image-guided patient setup corrections, automatic bony anatomy-based image registration could lead to target misalignment. Soft tissue-based image registration should be performed for accurate treatment delivery.« less

  1. Use of volume-targeted non-invasive bilevel positive airway pressure ventilation in a patient with amyotrophic lateral sclerosis*,**

    PubMed Central

    Diaz-Abad, Montserrat; Brown, John Edward

    2014-01-01

    Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease in which most patients die of respiratory failure. Although volume-targeted non-invasive bilevel positive airway pressure (BPAP) ventilation has been studied in patients with chronic respiratory failure of various etiologies, its use in ALS has not been reported. We present the case of a 66-year-old woman with ALS and respiratory failure treated with volume-targeted BPAP ventilation for 15 weeks. Weekly data downloads showed that disease progression was associated with increased respiratory muscle weakness, decreased spontaneous breathing, and increased use of non-invasive positive pressure ventilation, whereas tidal volume and minute ventilation remained relatively constant. PMID:25210968

  2. 3D-segmentation of the 18F-choline PET signal for target volume definition in radiation therapy of the prostate.

    PubMed

    Ciernik, I Frank; Brown, Derek W; Schmid, Daniel; Hany, Thomas; Egli, Peter; Davis, J Bernard

    2007-02-01

    Volumetric assessment of PET signals becomes increasingly relevant for radiotherapy (RT) planning. Here, we investigate the utility of 18F-choline PET signals to serve as a structure for semi-automatic segmentation for forward treatment planning of prostate cancer. 18F-choline PET and CT scans of ten patients with histologically proven prostate cancer without extracapsular growth were acquired using a combined PET/CT scanner. Target volumes were manually delineated on CT images using standard software. Volumes were also obtained from 18F-choline PET images using an asymmetrical segmentation algorithm. PTVs were derived from CT 18F-choline PET based clinical target volumes (CTVs) by automatic expansion and comparative planning was performed. As a read-out for dose given to non-target structures, dose to the rectal wall was assessed. Planning target volumes (PTVs) derived from CT and 18F-choline PET yielded comparable results. Optimal matching of CT and 18F-choline PET derived volumes in the lateral and cranial-caudal directions was obtained using a background-subtracted signal thresholds of 23.0+/-2.6%. In antero-posterior direction, where adaptation compensating for rectal signal overflow was required, optimal matching was achieved with a threshold of 49.5+/-4.6%. 3D-conformal planning with CT or 18F-choline PET resulted in comparable doses to the rectal wall. Choline PET signals of the prostate provide adequate spatial information amendable to standardized asymmetrical region growing algorithms for PET-based target volume definition for external beam RT.

  3. Analysis of radiation exposure for naval units of Operation Crossroads. Volume 2. (Appendix A) target ships. Technical report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weitz, R.; Thomas, C.; Klemm, J.

    1982-03-03

    External radiation doses are reconstructed for crews of support and target ships of Joint Task Force One at Operation CROSSROADS, 1946. Volume I describes the reconstruction methodology, which consists of modeling the radiation environment, to include the radioactivity of lagoon water, target ships, and support ship contamination; retracing ship paths through this environment; and calculating the doses to shipboard personnel. The USS RECLAIMER, a support ship, is selected as a representative ship to demonstrate this methodology. Doses for all other ships are summarized. Volume II (Appendix A) details the results for target ship personnel. Volume III (Appendix B) details themore » results for support ship personnel. Calculated doses for more than 36,000 personnel aboard support ships while at Bikini range from zero to 1.7 rem. Of those, approximately 34,000 are less than 0.5 rem. From the models provided, doses due to target ship reboarding and doses accrued after departure from Bikini can be calculated, based on the individual circumstances of exposure.« less

  4. Raytracing and Direct-Drive Targets

    NASA Astrophysics Data System (ADS)

    Schmitt, Andrew J.; Bates, Jason; Fyfe, David; Eimerl, David

    2013-10-01

    Accurate simulation of the effects of laser imprinting and drive asymmetries in directly driven targets requires the ability to distinguish between raytrace noise and the intensity structure produced by the spatial and temporal incoherence of optical smoothing. We have developed and implemented a smoother raytrace algorithm for our mpi-parallel radiation hydrodynamics code, FAST3D. The underlying approach is to connect the rays into either sheets (in 2D) or volume-enclosing chunks (in 3D) so that the absorbed energy distribution continuously covers the propagation area illuminated by the laser. We will describe the status and show the different scalings encountered in 2D and 3D problems as the computational size, parallelization strategy, and number of rays is varied. Finally, we show results using the method in current NIKE experimental target simulations and in proposed symmetric and polar direct-drive target designs. Supported by US DoE/NNSA.

  5. A fast automatic target detection method for detecting ships in infrared scenes

    NASA Astrophysics Data System (ADS)

    Özertem, Kemal Arda

    2016-05-01

    Automatic target detection in infrared scenes is a vital task for many application areas like defense, security and border surveillance. For anti-ship missiles, having a fast and robust ship detection algorithm is crucial for overall system performance. In this paper, a straight-forward yet effective ship detection method for infrared scenes is introduced. First, morphological grayscale reconstruction is applied to the input image, followed by an automatic thresholding onto the suppressed image. For the segmentation step, connected component analysis is employed to obtain target candidate regions. At this point, it can be realized that the detection is defenseless to outliers like small objects with relatively high intensity values or the clouds. To deal with this drawback, a post-processing stage is introduced. For the post-processing stage, two different methods are used. First, noisy detection results are rejected with respect to target size. Second, the waterline is detected by using Hough transform and the detection results that are located above the waterline with a small margin are rejected. After post-processing stage, there are still undesired holes remaining, which cause to detect one object as multi objects or not to detect an object as a whole. To improve the detection performance, another automatic thresholding is implemented only to target candidate regions. Finally, two detection results are fused and post-processing stage is repeated to obtain final detection result. The performance of overall methodology is tested with real world infrared test data.

  6. Variations of target volume definition and daily target volume localization in stereotactic body radiotherapy for early-stage non-small cell lung cancer patients under abdominal compression.

    PubMed

    Han, Chunhui; Sampath, Sagus; Schultheisss, Timothy E; Wong, Jeffrey Y C

    2017-01-01

    We aimed to compare gross tumor volumes (GTV) in 3-dimensional computed tomography (3DCT) simulation and daily cone beam CT (CBCT) with the internal target volume (ITV) in 4-dimensional CT (4DCT) simulation in stereotactic body radiotherapy (SBRT) treatment of patients with early-stage non-small cell lung cancer (NSCLC) under abdominal compression. We retrospectively selected 10 patients with NSCLC who received image-guided SBRT treatments under abdominal compression with daily CBCT imaging. GTVs were contoured as visible gross tumor on the planning 3DCT and daily CBCT, and ITVs were contoured using maximum intensity projection (MIP) images of the planning 4DCT. Daily CBCTs were registered with 3DCT and MIP images by matching of bony landmarks in the thoracic region to evaluate interfractional GTV position variations. Relative to MIP-based ITVs, the average 3DCT-based GTV volume was 66.3 ± 17.1% (range: 37.5% to 92.0%) (p < 0.01 in paired t-test), and the average CBCT-based GTV volume was 90.0 ± 6.7% (daily range: 75.7% to 107.1%) (p = 0.02). Based on bony anatomy matching, the center-of-mass coordinates for CBCT-based GTVs had maximum absolute shift of 2.4 mm (left-right), 7.0 mm (anterior-posterior [AP]), and 5.2 mm (superior-inferior [SI]) relative to the MIP-based ITV. CBCT-based GTVs had average overlapping ratio of 81.3 ± 11.2% (range: 45.1% to 98.9%) with the MIP-based ITV, and 57.7 ± 13.7% (range: 35.1% to 83.2%) with the 3DCT-based GTV. Even with abdominal compression, both 3DCT simulations and daily CBCT scans significantly underestimated the full range of tumor motion. In daily image-guided patient setup corrections, automatic bony anatomy-based image registration could lead to target misalignment. Soft tissue-based image registration should be performed for accurate treatment delivery. Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  7. Performance of the NIRS fast scanning system for heavy-ion radiotherapy.

    PubMed

    Furukawa, Takuji; Inaniwa, Taku; Sato, Shinji; Shirai, Toshiyuki; Takei, Yuka; Takeshita, Eri; Mizushima, Kota; Iwata, Yoshiyuki; Himukai, Takeshi; Mori, Shinichiro; Fukuda, Shigekazu; Minohara, Shinichi; Takada, Eiichi; Murakami, Takeshi; Noda, Koji

    2010-11-01

    A project to construct a new treatment facility, as an extension of the existing HIMAC facility, has been initiated for the further development of carbon-ion therapy at NIRS. This new treatment facility is equipped with a 3D irradiation system with pencil-beam scanning. The challenge of this project is to realize treatment of a moving target by scanning irradiation. To achieve fast rescanning within an acceptable irradiation time, the authors developed a fast scanning system. In order to verify the validity of the design and to demonstrate the performance of the fast scanning prior to use in the new treatment facility, a new scanning-irradiation system was developed and installed into the existing HIMAC physics-experiment course. The authors made strong efforts to develop (1) the fast scanning magnet and its power supply, (2) the high-speed control system, and (3) the beam monitoring. The performance of the system including 3D dose conformation was tested by using the carbon beam from the HIMAC accelerator. The performance of the fast scanning system was verified by beam tests. Precision of the scanned beam position was less than +/-0.5 mm. By cooperating with the planning software, the authors verified the homogeneity of the delivered field within +/-3% for the 3D delivery. This system took only 20 s to deliver the physical dose of 1 Gy to a spherical target having a diameter of 60 mm with eight rescans. In this test, the average of the spot-staying time was considerably reduced to 154 micros, while the minimum staying time was 30 micros. As a result of this study, the authors verified that the new scanning delivery system can produce an accurate 3D dose distribution for the target volume in combination with the planning software.

  8. Impact of Node Negative Target Volume Delineation on Contralateral Parotid Gland Dose Sparing Using IMRT in Head and Neck Cancer.

    PubMed

    Magnuson, William J; Urban, Erich; Bayliss, R Adam; Harari, Paul M

    2015-06-01

    There is considerable practice variation in treatment of the node negative (N0) contralateral neck in patients with head and neck cancer. In this study, we examined the impact of N0 neck target delineation volume on radiation dose to the contralateral parotid gland. Following institutional review board approval, 12 patients with head and neck cancer were studied. All had indications for treatment of the N0 neck, such as midline base of tongue or soft palate extension or advanced ipsilateral nodal disease. The N0 neck volumes were created using the Radiation Therapy Oncology Group head and neck contouring atlas. The physician-drawn N0 neck clinical target volume (CTV) was expanded by 25% to 200% to generate volume variation, followed by a 3-mm planning target volume (PTV) expansion. Surrounding organs at risk were contoured and complete intensity-modulated radiation therapy plans were generated for each N0 volume expansion. The median N0 target volume drawn by the radiation oncologist measured 93 cm(3) (range 71-145). Volumetric expansion of the N0 CTV by 25% to 200% increased the resultant mean dose to the contralateral parotid gland by 1.4 to 8.5 Gray (Gy). For example, a 4.1-mm increase in the N0 neck CTV translated to a 2.0-Gy dose increase to the parotid, 7.4 mm to a 4.5 Gy dose increase, and 12.5 mm to an 8.5 Gy dose increase, respectively. The treatment volume designated for the N0 neck has profound impact on resultant dose to the contralateral parotid gland. Variations of up to 15 mm are routine across physicians in target contouring, reflecting individual preference and training expertise. Depending on the availability of immobilization and image guidance techniques, experts commonly recommend 3 to 10 mm margin expansions to generate the PTV. Careful attention to the original volume of the N0 neck CTV, as well as expansion margins, is important in achieving effective contralateral gland sparing to reduce the resultant xerostomia and dysguesia that may ensue

  9. Fast targeted gene transfection and optogenetic modification of single neurons using femtosecond laser irradiation

    PubMed Central

    Antkowiak, Maciej; Torres-Mapa, Maria Leilani; Witts, Emily C.; Miles, Gareth B.; Dholakia, Kishan; Gunn-Moore, Frank J.

    2013-01-01

    A prevailing problem in neuroscience is the fast and targeted delivery of DNA into selected neurons. The development of an appropriate methodology would enable the transfection of multiple genes into the same cell or different genes into different neighboring cells as well as rapid cell selective functionalization of neurons. Here, we show that optimized femtosecond optical transfection fulfills these requirements. We also demonstrate successful optical transfection of channelrhodopsin-2 in single selected neurons. We extend the functionality of this technique for wider uptake by neuroscientists by using fast three-dimensional laser beam steering enabling an image-guided “point-and-transfect” user-friendly transfection of selected cells. A sub-second transfection timescale per cell makes this method more rapid by at least two orders of magnitude when compared to alternative single-cell transfection techniques. This novel technology provides the ability to carry out large-scale cell selective genetic studies on neuronal ensembles and perform rapid genetic programming of neural circuits. PMID:24257461

  10. Fast targeted gene transfection and optogenetic modification of single neurons using femtosecond laser irradiation.

    PubMed

    Antkowiak, Maciej; Torres-Mapa, Maria Leilani; Witts, Emily C; Miles, Gareth B; Dholakia, Kishan; Gunn-Moore, Frank J

    2013-11-21

    A prevailing problem in neuroscience is the fast and targeted delivery of DNA into selected neurons. The development of an appropriate methodology would enable the transfection of multiple genes into the same cell or different genes into different neighboring cells as well as rapid cell selective functionalization of neurons. Here, we show that optimized femtosecond optical transfection fulfills these requirements. We also demonstrate successful optical transfection of channelrhodopsin-2 in single selected neurons. We extend the functionality of this technique for wider uptake by neuroscientists by using fast three-dimensional laser beam steering enabling an image-guided "point-and-transfect" user-friendly transfection of selected cells. A sub-second transfection timescale per cell makes this method more rapid by at least two orders of magnitude when compared to alternative single-cell transfection techniques. This novel technology provides the ability to carry out large-scale cell selective genetic studies on neuronal ensembles and perform rapid genetic programming of neural circuits.

  11. MutScan: fast detection and visualization of target mutations by scanning FASTQ data.

    PubMed

    Chen, Shifu; Huang, Tanxiao; Wen, Tiexiang; Li, Hong; Xu, Mingyan; Gu, Jia

    2018-01-22

    Some types of clinical genetic tests, such as cancer testing using circulating tumor DNA (ctDNA), require sensitive detection of known target mutations. However, conventional next-generation sequencing (NGS) data analysis pipelines typically involve different steps of filtering, which may cause miss-detection of key mutations with low frequencies. Variant validation is also indicated for key mutations detected by bioinformatics pipelines. Typically, this process can be executed using alignment visualization tools such as IGV or GenomeBrowse. However, these tools are too heavy and therefore unsuitable for validating mutations in ultra-deep sequencing data. We developed MutScan to address problems of sensitive detection and efficient validation for target mutations. MutScan involves highly optimized string-searching algorithms, which can scan input FASTQ files to grab all reads that support target mutations. The collected supporting reads for each target mutation will be piled up and visualized using web technologies such as HTML and JavaScript. Algorithms such as rolling hash and bloom filter are applied to accelerate scanning and make MutScan applicable to detect or visualize target mutations in a very fast way. MutScan is a tool for the detection and visualization of target mutations by only scanning FASTQ raw data directly. Compared to conventional pipelines, this offers a very high performance, executing about 20 times faster, and offering maximal sensitivity since it can grab mutations with even one single supporting read. MutScan visualizes detected mutations by generating interactive pile-ups using web technologies. These can serve to validate target mutations, thus avoiding false positives. Furthermore, MutScan can visualize all mutation records in a VCF file to HTML pages for cloud-friendly VCF validation. MutScan is an open source tool available at GitHub: https://github.com/OpenGene/MutScan.

  12. A New Suggestion for the Radiation Target Volume After a Subtotal Gastrectomy in Patients With Stomach Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nam, Heerim; Lim, Do Hoon; Kim, Sung

    2008-06-01

    Purpose: To compare treatment results between the use of two different radiation fields including and excluding remnant stomach and suggest new target volumes excluding remnant stomach after subtotal gastrectomy (STG) in patients with stomach cancer. Methods and Materials: We retrospectively analyzed 291 patients treated with adjuvant chemoradiotherapy after STG and D2 dissection at the Samsung Medical Center, Seoul, South Korea. Eighty-three patients registered from 1995 to 1997 underwent irradiation according to the INT 0116 protocol that recommended the inclusion of remnant stomach within the target volume (Group A). After this period, we excluded remnant stomach from the target volume formore » 208 patients (Group B). Median follow-up was 67 months. Results: Treatment failure developed in 93 patients (32.0%). Local and regional recurrence rates for Group A vs. Group B were 10.8% vs. 5.3% (p = not significant) and 9.6% vs. 6.3% (p = not significant), and recurrence rates for remnant stomach were 7.2% vs. 1.4% (p = 0.018), respectively. Overall and disease-free survival rates were not different between the two groups. Grade 3 or 4 vomiting and diarrhea developed more frequently in Group A than Group B (4.8% vs. 1.4% and 6.0% vs. 1.9%, respectively; p = 0.012; p < 0.001). Conclusion: Exclusion of remnant stomach from the radiation field had no effect on failure rates or survival, and a low complication rate occurred in patients treated excluding remnant stomach. We suggest that remnant stomach be excluded from the radiation target volume for patients with stomach cancer who undergo STG and D2 dissection.« less

  13. Performance of Leak Compensation in All-Age ICU Ventilators During Volume-Targeted Neonatal Ventilation: A Lung Model Study.

    PubMed

    Itagaki, Taiga; Bennett, Desmond J; Chenelle, Christopher T; Fisher, Daniel F; Kacmarek, Robert M

    2017-01-01

    Volume-targeted ventilation is increasingly used in low birthweight infants because of the potential for reducing volutrauma and avoiding hypocapnea. However, it is not known what level of air leak is acceptable during neonatal volume-targeted ventilation when leak compensation is activated concurrently. Four ICU ventilators (Servo-i, PB980, V500, and Avea) were compared in available invasive volume-targeted ventilation modes (pressure control continuous spontaneous ventilation [PC-CSV] and pressure control continuous mandatory ventilation [PC-CMV]). The Servo-i and PB980 were tested with (+) and without (-) their proximal flow sensor. The V500 and Avea were tested with their proximal flow sensor as indicated by their manufacturers. An ASL 5000 lung model was used to simulate 4 neonatal scenarios (body weight 0.5, 1, 2, and 4 kg). The ASL 5000 was ventilated via an endotracheal tube with 3 different leaks. Two minutes of data were collected after each change in leak level, and the asynchrony index was calculated. Tidal volume (V T ) before and after the change in leak was assessed. The differences in delivered V T between before and after the change in leak were within ±5% in all scenarios with the PB980 (-/+) and V500. With the Servo-i (-/+), baseline V T was ≥10% greater than set V T during PC-CSV, and delivered V T markedly changed with leak. The Avea demonstrated persistent high V T in all leak scenarios. Across all ventilators, the median asynchrony index was 1% (interquartile range 0-27%) in PC-CSV and 1.8% (0-45%) in PC-CMV. The median asynchrony index was significantly higher in the Servo-i (-/+) than in the PB980 (-/+) and V500 in 1 and 2 kg scenarios during PC-CSV and PC-CMV. The PB980 and V500 were the only ventilators to acclimate to all leak scenarios and achieve targeted V T . Further clinical investigation is needed to validate the use of leak compensation during neonatal volume-targeted ventilation. Copyright © 2017 by Daedalus Enterprises.

  14. Intravesical markers for delineation of target volume during external focal irradiation of bladder carcinomas.

    PubMed

    Hulshof, Maarten C C M; van Andel, George; Bel, Arjen; Gangel, Pieter; van de Kamer, Jeroen B

    2007-07-01

    A clip forceps was developed which can insert markers at the border of a bladder tumour through a rigid cystoscope. This technique proved to be simple and safe and is of help for delineation of the target volume during CT simulation for focal boost irradiation of bladder cancer.

  15. SU-E-T-578: On Definition of Minimum and Maximum Dose for Target Volume

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gong, Y; Yu, J; Xiao, Y

    Purpose: This study aims to investigate the impact of different minimum and maximum dose definitions in radiotherapy treatment plan quality evaluation criteria by using tumor control probability (TCP) models. Methods: Dosimetric criteria used in RTOG 1308 protocol are used in the investigation. RTOG 1308 is a phase III randomized trial comparing overall survival after photon versus proton chemoradiotherapy for inoperable stage II-IIIB NSCLC. The prescription dose for planning target volume (PTV) is 70Gy. Maximum dose (Dmax) should not exceed 84Gy and minimum dose (Dmin) should not go below 59.5Gy in order for the plan to be “per protocol” (satisfactory).A mathematicalmore » model that simulates the characteristics of PTV dose volume histogram (DVH) curve with normalized volume is built. The Dmax and Dmin are noted as percentage volumes Dη% and D(100-δ)%, with η and d ranging from 0 to 3.5. The model includes three straight line sections and goes through four points: D95%= 70Gy, Dη%= 84Gy, D(100-δ)%= 59.5 Gy, and D100%= 0Gy. For each set of η and δ, the TCP value is calculated using the inhomogeneously irradiated tumor logistic model with D50= 74.5Gy and γ50=3.52. Results: TCP varies within 0.9% with η; and δ values between 0 and 1. With η and η varies between 0 and 2, TCP change was up to 2.4%. With η and δ variations from 0 to 3.5, maximum of 8.3% TCP difference is seen. Conclusion: When defined maximum and minimum volume varied more than 2%, significant TCP variations were seen. It is recommended less than 2% volume used in definition of Dmax or Dmin for target dosimetric evaluation criteria. This project was supported by NIH grants U10CA180868, U10CA180822, U24CA180803, U24CA12014 and PA CURE Grant.« less

  16. Clinical target volume delineation in glioblastomas: pre-operative versus post-operative/pre-radiotherapy MRI

    PubMed Central

    Farace, P; Giri, M G; Meliadò, G; Amelio, D; Widesott, L; Ricciardi, G K; Dall'Oglio, S; Rizzotti, A; Sbarbati, A; Beltramello, A; Maluta, S; Amichetti, M

    2011-01-01

    Objectives Delineation of clinical target volume (CTV) is still controversial in glioblastomas. In order to assess the differences in volume and shape of the radiotherapy target, the use of pre-operative vs post-operative/pre-radiotherapy T1 and T2 weighted MRI was compared. Methods 4 CTVs were delineated in 24 patients pre-operatively and post-operatively using T1 contrast-enhanced (T1PRECTV and T1POSTCTV) and T2 weighted images (T2PRECTV and T2POSTCTV). Pre-operative MRI examinations were performed the day before surgery, whereas post-operative examinations were acquired 1 month after surgery and before chemoradiation. A concordance index (CI) was defined as the ratio between the overlapping and composite volumes. Results The volumes of T1PRECTV and T1POSTCTV were not statistically different (248 ± 88 vs 254 ± 101), although volume differences >100 cm3 were observed in 6 out of 24 patients. A marked increase due to tumour progression was shown in three patients. Three patients showed a decrease because of a reduced mass effect. A significant reduction occurred between pre-operative and post-operative T2 volumes (139 ± 68 vs 78 ± 59). Lack of concordance was observed between T1PRECTV and T1POSTCTV (CI = 0.67 ± 0.09), T2PRECTV and T2POSTCTV (CI = 0.39 ± 0.20) and comparing the portion of the T1PRECTV and T1POSTCTV not covered by that defined on T2PRECTV images (CI = 0.45 ± 0.16 and 0.44 ± 0.17, respectively). Conclusion Using T2 MRI, huge variations can be observed in peritumoural oedema, which are probably due to steroid treatment. Using T1 MRI, brain shifts after surgery and possible progressive enhancing lesions produce substantial differences in CTVs. Our data support the use of post-operative/pre-radiotherapy T1 weighted MRI for planning purposes. PMID:21045069

  17. ESTRO ACROP guidelines for target volume definition in the treatment of locally advanced non-small cell lung cancer.

    PubMed

    Nestle, Ursula; De Ruysscher, Dirk; Ricardi, Umberto; Geets, Xavier; Belderbos, Jose; Pöttgen, Christoph; Dziadiuszko, Rafal; Peeters, Stephanie; Lievens, Yolande; Hurkmans, Coen; Slotman, Ben; Ramella, Sara; Faivre-Finn, Corinne; McDonald, Fiona; Manapov, Farkhad; Putora, Paul Martin; LePéchoux, Cécile; Van Houtte, Paul

    2018-04-01

    Radiotherapy (RT) plays a major role in the curative treatment of locally advanced non-small cell lung cancer (NSCLC). Therefore, the ACROP committee was asked by the ESTRO to provide recommendations on target volume delineation for standard clinical scenarios in definitive (chemo)radiotherapy (RT) and adjuvant RT for locally advanced NSCLC. The guidelines given here are a result of the evaluation of a structured questionnaire followed by a consensus discussion, voting and writing procedure within the committee. Hence, we provide advice for methods and time-points of diagnostics and imaging before the start of treatment planning and for the mandatory and optional imaging to be used for planning itself. Concerning target volumes, recommendations are given for GTV delineation of primary tumour and lymph nodes followed by issues related to the delineation of CTVs for definitive and adjuvant radiotherapy. In the context of PTV delineation, recommendations about the management of geometric uncertainties and target motion are given. We further provide our opinions on normal tissue delineation and organisational and responsibility questions in the process of target volume delineation. This guideline intends to contribute to the standardisation and optimisation of the process of RT treatment planning for clinical practice and prospective studies. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Fasting does not induce gastric emptying in rats.

    PubMed

    Brito, Marcus Vinicius Henriques; Yasojima, Edson Yuzur; Teixeira, Renan Kleber Costa; Houat, Abdallah de Paula; Yamaki, Vitor Nagai; Costa, Felipe Lobato da Silva

    2015-03-01

    To evaluate the effect of fasting on gastric emptying in mice. Twenty-eight mice were distributed into three study groups: a normal group (N=4): normal standard animals; a total fasting group (N=12): subjected to food and water deprivation and a partial fasting group (N=12): subjected to food deprivation only. The fasting groups were subdivided into three subgroups of four animals each, according to the date of euthanasia: 24, 48 and 72 hours. Was analyzed: the gastric volume, degree of the gastric wall distention and the presence of food debris in gastrointestinal tract. The mean gastric volume was 1601 mm3 in the normal group, 847 mm3 in total fasting group and 997 mm3 in partial fasting group. There was difference between the fasting groups in any analyzed period (p<0.05). Regarding the presence of food debris in the gastrointestinal tract and the degree of distension of the stomach, there was no difference between the groups that underwent total or partial fasting (p>0.05). Total fasting or only-solids deprivation does not induce gastric emptying in mice.

  19. P04.02 Analysis of 18F-DOPA PET imaging for target volume definition in patients with recurrent glioblastoma treated with proton therapy

    PubMed Central

    Amelio, D.; Scartoni, D.; Palucci, A.; Vennarini, S.; Giacomelli, I.; Lemoine, S.; Donner, D.; Farace, P.; Chierichetti, F.; Amichetti, M.

    2017-01-01

    Abstract Introduction: Target volume definition is of critical relevance when re-irradiation is delivered and steep dose gradient irradiation techniques, such as proton therapy (PT), are employed. Aim of the study is to investigate the impact of 18F-DOPA on target volume contouring in recurrent glioblastoma (rGBM) patients (pts) undergoing re-irradiation with PT. MATERIAL AND METHODS: We investigated the differences in volume and relationship of magnetic resonance imaging (MRI)- vs. DOPA PET-derived gross tumor volumes (GTVs) of 14 rGBM pts re-irradiated with PT between January and November 2016. All pts had been previously treated with photon radiotherapy (60 Gy) with concomitant and adjuvant temozolomide. All the pts received morphological MRI with contrast enhancement medium administration and 18F-DOPA PET-CT study. We used the pathological distribution of 18F-DOPA in brain tissue to identify the so-called Biological Tumor Volume (BTV). Such areas were assessed using a tumor to normal brain ratio > 2. Moreover, any area of contrast enhancement on MRI was used to identify the MRI-based GTV (MRGTV). Definitive GTV included MRGTV plus BTV. Clinical target volume was generated by adding to GTV a 3-mm uniform margin manually corrected in proximity of anatomical barriers. CTV was expanded by 4 mm to create planning target volume. All pts received 36 GyRBE in 18 fractions. Mean values of differently delineated GTVs were compared each other by paired Student’s t-test; p < 0.05 was considered significant. To further compare MRGTV and BTV, the overlapping (MRGTV ^ BTV) and the composite (MRGTV U BTV) volumes were calculated, and a concordance index (CI) was defined as the ratio between the overlap and composite volumes. Results: MRGTV (mean 14.9 ± 14.5 cc) was larger than BTV (mean 10.9 ± 9.8 cc) although this difference was not statistically significant. The composite volume (mean 20.9 ± 14.7 cc) was significantly larger than each single volume (p < 0

  20. Child-targeted fast-food television advertising exposure is linked with fast-food intake among pre-school children.

    PubMed

    Dalton, Madeline A; Longacre, Meghan R; Drake, Keith M; Cleveland, Lauren P; Harris, Jennifer L; Hendricks, Kristy; Titus, Linda J

    2017-06-01

    To determine whether exposure to child-targeted fast-food (FF) television (TV) advertising is associated with children's FF intake in a non-experimental setting. Cross-sectional survey conducted April-December 2013. Parents reported their pre-school child's TV viewing time, channels watched and past-week FF consumption. Responses were combined with a list of FF commercials (ads) aired on children's TV channels during the same period to calculate children's exposure to child-targeted TV ads for the following chain FF restaurants: McDonald's, Subway and Wendy's (MSW). Paediatric and Women, Infants, and Children (WIC) clinics in New Hampshire, USA. Parents (n 548) with a child of pre-school age. Children's mean age was 4·4 years; 43·2 % ate MSW in the past week. Among the 40·8 % exposed to MSW ads, 23·3 % had low, 34·2 % moderate and 42·5 % high exposure. McDonald's accounted for over 70 % of children's MSW ad exposure and consumption. Children's MSW consumption was significantly associated with their ad exposure, but not overall TV viewing time. After adjusting for demographics, socio-economic status and other screen time, moderate MSW ad exposure was associated with a 31 % (95 % CI 1·12, 1·53) increase and high MSW ad exposure with a 26 % (95 % CI 1·13, 1·41) increase in the likelihood of consuming MSW in the past week. Further adjustment for parent FF consumption did not change the findings substantially. Exposure to child-targeted FF TV advertising is positively associated with FF consumption among children of pre-school age, highlighting the vulnerability of young children to persuasive advertising and supporting recommendations to limit child-directed FF marketing.

  1. Child-targeted fast-food television advertising exposure is linked with fast-food intake among pre-school children

    PubMed Central

    Dalton, Madeline A; Longacre, Meghan R; Drake, Keith M; Cleveland, Lauren P; Harris, Jennifer L; Hendricks, Kristy; Titus, Linda J

    2017-01-01

    Objective To determine whether exposure to child-targeted fast-food (FF) television (TV) advertising is associated with children’s FF intake in a non-experimental setting. Design Cross-sectional survey conducted April–December 2013. Parents reported their pre-school child’s TV viewing time, channels watched and past-week FF consumption. Responses were combined with a list of FF commercials (ads) aired on children’s TV channels during the same period to calculate children’s exposure to child-targeted TV ads for the following chain FF restaurants: McDonald’s, Subway and Wendy’s (MSW). Setting Paediatric and Women, Infants, and Children (WIC) clinics in New Hampshire, USA. Subjects Parents (n 548) with a child of pre-school age. Results Children’s mean age was 4·4 years; 43·2 % ate MSW in the past week. Among the 40·8 % exposed to MSW ads, 23·3 % had low, 34·2 % moderate and 42·5 % high exposure. McDonald’s accounted for over 70 % of children’s MSW ad exposure and consumption. Children’s MSW consumption was significantly associated with their ad exposure, but not overall TV viewing time. After adjusting for demographics, socio-economic status and other screen time, moderate MSW ad exposure was associated with a 31 % (95 % CI 1·12, 1·53) increase and high MSW ad exposure with a 26 % (95 % CI 1·13, 1·41) increase in the likelihood of consuming MSW in the past week. Further adjustment for parent FF consumption did not change the findings substantially. Conclusions Exposure to child-targeted FF TV advertising is positively associated with FF consumption among children of pre-school age, highlighting the vulnerability of young children to persuasive advertising and supporting recommendations to limit child-directed FF marketing. PMID:28416041

  2. Validation of a 4D-PET Maximum Intensity Projection for Delineation of an Internal Target Volume

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Callahan, Jason, E-mail: jason.callahan@petermac.org; Kron, Tomas; Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne

    2013-07-15

    Purpose: The delineation of internal target volumes (ITVs) in radiation therapy of lung tumors is currently performed by use of either free-breathing (FB) {sup 18}F-fluorodeoxyglucose-positron emission tomography-computed tomography (FDG-PET/CT) or 4-dimensional (4D)-CT maximum intensity projection (MIP). In this report we validate the use of 4D-PET-MIP for the delineation of target volumes in both a phantom and in patients. Methods and Materials: A phantom with 3 hollow spheres was prepared surrounded by air then water. The spheres and water background were filled with a mixture of {sup 18}F and radiographic contrast medium. A 4D-PET/CT scan was performed of the phantom whilemore » moving in 4 different breathing patterns using a programmable motion device. Nine patients with an FDG-avid lung tumor who underwent FB and 4D-PET/CT and >5 mm of tumor motion were included for analysis. The 3 spheres and patient lesions were contoured by 2 contouring methods (40% of maximum and PET edge) on the FB-PET, FB-CT, 4D-PET, 4D-PET-MIP, and 4D-CT-MIP. The concordance between the different contoured volumes was calculated using a Dice coefficient (DC). The difference in lung tumor volumes between FB-PET and 4D-PET volumes was also measured. Results: The average DC in the phantom using 40% and PET edge, respectively, was lowest for FB-PET/CT (DCAir = 0.72/0.67, DCBackground 0.63/0.62) and highest for 4D-PET/CT-MIP (DCAir = 0.84/0.83, DCBackground = 0.78/0.73). The average DC in the 9 patients using 40% and PET edge, respectively, was also lowest for FB-PET/CT (DC = 0.45/0.44) and highest for 4D-PET/CT-MIP (DC = 0.72/0.73). In the 9 lesions, the target volumes of the FB-PET using 40% and PET edge, respectively, were on average 40% and 45% smaller than the 4D-PET-MIP. Conclusion: A 4D-PET-MIP produces volumes with the highest concordance with 4D-CT-MIP across multiple breathing patterns and lesion sizes in both a phantom and among patients. Freebreathing PET/CT consistently

  3. Method modification of the Legipid® Legionella fast detection test kit.

    PubMed

    Albalat, Guillermo Rodríguez; Broch, Begoña Bedrina; Bono, Marisa Jiménez

    2014-01-01

    Legipid(®) Legionella Fast Detection is a test based on combined magnetic immunocapture and enzyme-immunoassay (CEIA) for the detection of Legionella in water. The test is based on the use of anti-Legionella antibodies immobilized on magnetic microspheres. Target microorganism is preconcentrated by filtration. Immunomagnetic analysis is applied on these preconcentrated water samples in a final test portion of 9 mL. The test kit was certified by the AOAC Research Institute as Performance Tested Method(SM) (PTM) No. 111101 in a PTM validation which certifies the performance claims of the test method in comparison to the ISO reference method 11731-1998 and the revision 11731-2004 "Water Quality: Detection and Enumeration of Legionella pneumophila" in potable water, industrial water, and waste water. The modification of this test kit has been approved. The modification includes increasing the target analyte from L. pneumophila to Legionella species and adding an optical reader to the test method. In this study, 71 strains of Legionella spp. other than L. pneumophila were tested to determine its reactivity with the kit based on CEIA. All the strains of Legionella spp. tested by the CEIA test were confirmed positive by reference standard method ISO 11731. This test (PTM 111101) has been modified to include a final optical reading. A methods comparison study was conducted to demonstrate the equivalence of this modification to the reference culture method. Two water matrixes were analyzed. Results show no statistically detectable difference between the test method and the reference culture method for the enumeration of Legionella spp. The relative level of detection was 93 CFU/volume examined (LOD50). For optical reading, the LOD was 40 CFU/volume examined and the LOQ was 60 CFU/volume examined. Results showed that the test Legipid Legionella Fast Detection is equivalent to the reference culture method for the enumeration of Legionella spp.

  4. A Fully Automated Supraglacial lake area and volume Tracking ("FAST") algorithm: development and application using MODIS imagery of West Greenland

    NASA Astrophysics Data System (ADS)

    Williamson, Andrew; Arnold, Neil; Banwell, Alison; Willis, Ian

    2017-04-01

    Supraglacial lakes (SGLs) on the Greenland Ice Sheet (GrIS) influence ice dynamics if draining rapidly by hydrofracture, which can occur in under 24 hours. MODerate-resolution Imaging Spectroradiometer (MODIS) data are often used to investigate SGLs, including calculating SGL area changes through time, but no existing work presents a method that tracks changes in individual (and total) SGL volume in MODIS imagery over a melt season. Here, we present such a method. First, we tested three automated approaches to derive SGL areas from MODIS imagery by comparing calculated areas for the Paakitsoq and Store Glacier regions in West Greenland with areas derived from Landsat-8 (LS8) images. Second, we applied a physically-based depth-calculation algorithm to the pixels within the SGL boundaries from the best performing method, and validated the resultant depths with those calculated using the same method applied to LS8 imagery. Our results indicated that SGL areas are most accurately generated using dynamic thresholding of MODIS band 1 (red) with a 0.640 threshold value. Calculated SGL area, depth and volume values from MODIS were closely comparable to those derived from LS8. The best performing area- and depth-detection methods were then incorporated into a Fully Automated SGL Tracking ("FAST") algorithm that tracks individual SGLs between successive MODIS images. It identified 43 (Paakitsoq) and 19 (Store Glacier) rapidly draining SGLs during 2014, representing 21% and 15% of the respective total SGL populations, including some clusters of rapidly draining SGLs. We found no relationship between the water volumes contained within these rapidly draining SGLs and the ice thicknesses beneath them, indicating that a critical water volume linearly related to ice thickness cannot explain the incidence of rapid drainage. The FAST algorithm, which we believe to be the most comprehensive SGL tracking algorithm developed to date, has the potential to investigate statistical

  5. Facial Contouring by Targeted Restoration of Facial Fat Compartment Volume: The Midface.

    PubMed

    Wang, Wenjin; Xie, Yun; Huang, Ru-Lin; Zhou, Jia; Tanja, Herrler; Zhao, Peijuan; Cheng, Chen; Zhou, Sizheng; Pu, Lee L Q; Li, Qingfeng

    2017-03-01

    Recent anatomical findings have suggested that facial fat distribution is complex and changes with age. Here, the authors developed a grafting technique based on the physiologic distribution and volume changes of facial fat compartments to achieve a youthful and natural-appearing face. Forty cadaveric hemifaces were used for the dissection of fat compartments and neurovascular structures in the midface area. Seventy-eight patients were treated for cheek atrophy using the authors' targeted restoration of midface fat compartment volume. The outcome was evaluated by a two-dimensional assessment, malar lipoatrophy assessment, and a satisfaction survey. The medial and lateral parts of the deep medial cheek fat compartment were separated by a septum arising from the lateral border of the levator anguli oris muscle. The angular vein traveled between the deep medial cheek fat compartment and the buccal fat pad, 12 mm from the maxilla. A total volume of 29.3 ml of fat was grafted per cheek for each patient. A 12-month follow-up revealed an average volume augmentation rate of 27.1 percent. Pleasing and elevated anterior projection of the cheek and ameliorated nasolabial groove were still obvious by 12 months after the procedure. In total, 95.2 percent of the patients were satisfied with their results. The present study provides the anatomical and clinical basis for the concept of compartmentally based fat grafting. It allows for the restoration of facial fat volume close to the physiologic state. With this procedure, a natural and youthful facial contour could be rebuilt with a high satisfaction rate. Therapeutic, IV.

  6. Poster - 36: Effect of Planning Target Volume Coverage on the Dose Delivered in Lung Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dekker, Chris; Wierzbicki, Marcin

    2016-08-15

    Purpose: In lung radiotherapy, breathing motion may be encompassed by contouring the internal target volume (ITV). Remaining uncertainties are included in a geometrical expansion to the planning target volume (PTV). In IMRT, the treatment is then optimized until a desired PTV fraction is covered by the appropriate dose. The resulting beams often carry high fluence in the PTV margin to overcome low lung density and to generate steep dose gradients. During treatment, the high density tumour can enter the PTV margin, potentially increasing target dose. Thus, planning lung IMRT with a reduced PTV dose may still achieve the desired ITVmore » dose during treatment. Methods: A retrospective analysis was carried out with 25 IMRT plans prescribed to 63 Gy in 30 fractions. The plans were re-normalized to cover various fractions of the PTV by different isodose lines. For each case, the isocentre was moved using 125 shifts derived from all 3D combinations of 0 mm, (PTV margin - 1 mm), and PTV margin. After each shift, the dose was recomputed to approximate the delivered dose. Results and Conclusion: Our plans typically cover 95% of the PTV by 95% of the dose. Reducing the PTV covered to 94% did not significantly reduce the delivered ITV doses for (PTV margin - 1 mm) shifts. Target doses were reduced significantly for all other shifts and planning goals studied. Thus, a reduced planning goal will likely deliver the desired target dose as long as the ITV rarely enters the last mm of the PTV margin.« less

  7. Using injectable hydrogel markers to assess resimulation for boost target volume definition in a patient undergoing whole-breast radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patel, Henal; Goyal, Sharad; Kim, Leonard, E-mail: kimlh@rutgers.edu

    Several publications have recommended that patients undergoing whole-breast radiotherapy be resimulated for boost planning. The rationale for this is that the seroma may be smaller when compared with the initial simulation. However, the decision remains whether to use the earlier or later images to define an appropriate boost target volume. A patient undergoing whole-breast radiotherapy had new, injectable, temporary hydrogel fiducial markers placed 1 to 3 cm from the seroma at the time of initial simulation. The patient was resimulated 4.5 weeks later for conformal photon boost planning. Computed tomography (CT) scans acquired at the beginning and the end ofmore » whole-breast radiotherapy showed that shrinkage of the lumpectomy cavity was not matched by a corresponding reduction in the surrounding tissue volume, as demarcated by hydrogel markers. This observation called into question the usual interpretation of cavity shrinkage for boost target definition. For this patient, it was decided to define the boost target volume on the initial planning CT instead of the new CT.« less

  8. Fast and efficient three-step target-specific curing of a virulence plasmid in Salmonella enterica.

    PubMed

    de Moraes, Marcos H; Teplitski, Max

    2015-12-01

    Virulence plasmids borne by serovars of Salmonella enterica carry genes involved in its pathogenicity, as well as other functions. Characterization of phenotypes associated with virulence plasmids requires a system for efficiently curing strains of their virulence plasmids. Here, we developed a 3-step protocol for targeted curing of virulence plasmids. The protocol involves insertion of an I-SecI restriction site linked to an antibiotic resistance gene into the target plasmid using λ-Red mutagenesis, followed by the transformation with a temperature-sensitive auxiliary plasmid which carries I-SecI nuclease expressed from a tetracycline-inducible promoter. Finally, the auxiliary plasmid is removed by incubation at 42 °C and the plasmid-less strains are verified on antibiotic-containing media. This method is fast and very efficient: over 90 % of recovered colonies lacked their virulence plasmid.

  9. Improving detection of low SNR targets using moment-based detection

    NASA Astrophysics Data System (ADS)

    Young, Shannon R.; Steward, Bryan J.; Hawks, Michael; Gross, Kevin C.

    2016-05-01

    Increases in the number of cameras deployed, frame rate, and detector array sizes have led to a dramatic increase in the volume of motion imagery data that is collected. Without a corresponding increase in analytical manpower, much of the data is not analyzed to full potential. This creates a need for fast, automated, and robust methods for detecting signals of interest. Current approaches fall into two categories: detect-before-track (DBT), which are fast but often poor at detecting dim targets, and track-before-detect (TBD) methods which can offer better performance but are typically much slower. This research seeks to contribute to the near real time detection of low SNR, unresolved moving targets through an extension of earlier work on higher order moments anomaly detection, a method that exploits both spatial and temporal information but is still computationally efficient and massively parallelizable. It was found that intelligent selection of parameters can improve probability of detection by as much as 25% compared to earlier work with higherorder moments. The present method can reduce detection thresholds by 40% compared to the Reed-Xiaoli anomaly detector for low SNR targets (for a given probability of detection and false alarm).

  10. Evaluation of potential internal target volume of liver tumors using cine-MRI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akino, Yuichi, E-mail: akino@radonc.med.osaka-u.ac.jp; Oh, Ryoong-Jin; Masai, Norihisa

    2014-11-01

    Purpose: Four-dimensional computed tomography (4DCT) is widely used for evaluating moving tumors, including lung and liver cancers. For patients with unstable respiration, however, the 4DCT may not visualize tumor motion properly. High-speed magnetic resonance imaging (MRI) sequences (cine-MRI) permit direct visualization of respiratory motion of liver tumors without considering radiation dose exposure to patients. Here, the authors demonstrated a technique for evaluating internal target volume (ITV) with consideration of respiratory variation using cine-MRI. Methods: The authors retrospectively evaluated six patients who received stereotactic body radiotherapy (SBRT) to hepatocellular carcinoma. Before acquiring planning CT, sagittal and coronal cine-MRI images were acquiredmore » for 30 s with a frame rate of 2 frames/s. The patient immobilization was conducted under the same condition as SBRT. Planning CT images were then acquired within 15 min from cine-MRI image acquisitions, followed by a 4DCT scan. To calculate tumor motion, the motion vectors between two continuous frames of cine-MRI images were calculated for each frame using the pyramidal Lucas–Kanade method. The target contour was delineated on one frame, and each vertex of the contour was shifted and copied onto the following frame using neighboring motion vectors. 3D trajectory data were generated with the centroid of the contours on sagittal and coronal images. To evaluate the accuracy of the tracking method, the motion of clearly visible blood vessel was analyzed with the motion tracking and manual detection techniques. The target volume delineated on the 50% (end-exhale) phase of 4DCT was translated with the trajectory data, and the distribution of the occupancy probability of target volume was calculated as potential ITV (ITV {sub Potential}). The concordance between ITV {sub Potential} and ITV estimated with 4DCT (ITV {sub 4DCT}) was evaluated using the Dice’s similarity coefficient (DSC

  11. [Microscopic extensions of head and neck squamous cell carcinomas: impact for clinical target volume definition].

    PubMed

    Fleury, B; Thariat, J; Barnoud, R; Buiret, G; Lebreton, F; Bancel, B; Poupart, M; Devouassoux-Shisheboran, M

    2014-11-01

    To assess microscopic extensions of head and neck squamous cell carcinomas aiming at a proposal for target volumes of radiation therapy. Surgical specimens were prospectively analysed macroscopically and microscopically. Tumour borders were identified per macroscopic visual examination and inked on stained slides. Then microscopic implants (perineural or lymphatic involvement, or in situ carcinomas) were looked for with an optic microscope in the macroscopic healthy tissue surrounding the tumour. The maximal length from tumour border was correlated with the maximal length of macroscopically healthy tissues assessable. Twenty-one specimens were analysed and 12 were locally advanced tumours. Mean and median maximal microscopic extensions were 2.9 and 1.0mm (0-15mm), respectively. The 90th and 95th percentiles were 5 and 11mm, respectively. The ratio between healthy tissue length and maximal microscopic tumour extension was 10%. No correlation was found with tumour grade or volume. The presence of microscopic tumour was unlikely after 5mm from macroscopic tumour (≤5% of patients in this series) but should be assessed along with other histoclinical factors and particularities of tumour behaviour by anatomic site. A rigorous terminology should authorize a relevant appreciation of local risk of recurrence, particularly in adjuvant setting or for clinical target volume definition. Larger and more homogenous confirmatory series are needed. Copyright © 2014. Published by Elsevier SAS.

  12. The application of positron emission tomography/computed tomography in radiation treatment planning: effect on gross target volume definition and treatment management.

    PubMed

    Iğdem, S; Alço, G; Ercan, T; Unalan, B; Kara, B; Geceer, G; Akman, C; Zengin, F O; Atilla, S; Okkan, S

    2010-04-01

    To analyse the effect of the use of molecular imaging on gross target volume (GTV) definition and treatment management. Fifty patients with various solid tumours who underwent positron emission tomography (PET)/computed tomography (CT) simulation for radiotherapy planning from 2006 to 2008 were enrolled in this study. First, F-18 fluorodeoxyglucose (FDG)-PET and CT scans of the treatment site in the treatment position and then a whole body scan were carried out with a dedicated PET/CT scanner and fused thereafter. FDG-avid primary tumour and lymph nodes were included into the GTV. A multidisciplinary team defined the target volume, and contouring was carried out by a radiation oncologist using visual methods. To compare the PET/CT-based volumes with CT-based volumes, contours were drawn on CT-only data with the help of site-specific radiologists who were blind to the PET/CT results after a median time of 7 months. In general, our PET/CT volumes were larger than our CT-based volumes. This difference was significant in patients with head and neck cancers. Major changes (> or =25%) in GTV delineation were observed in 44% of patients. In 16% of cases, PET/CT detected incidental second primaries and metastatic disease, changing the treatment strategy from curative to palliative. Integrating functional imaging with FDG-PET/CT into the radiotherapy planning process resulted in major changes in a significant proportion of our patients. An interdisciplinary approach between imaging and radiation oncology departments is essential in defining the target volumes. Copyright 2010 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  13. Delineation of Internal Mammary Nodal Target Volumes in Breast Cancer Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jethwa, Krishan R.; Kahila, Mohamed M.; Hunt, Katie N.

    Purpose: The optimal clinical target volume for internal mammary (IM) node irradiation is uncertain in an era of increasingly conformal volume-based treatment planning for breast cancer. We mapped the location of gross internal mammary lymph node (IMN) metastases to identify areas at highest risk of harboring occult disease. Methods and Materials: Patients with axial imaging of IMN disease were identified from a breast cancer registry. The IMN location was transferred onto the corresponding anatomic position on representative axial computed tomography images of a patient in the treatment position and compared with consensus group guidelines of IMN target delineation. Results: Themore » IMN location in 67 patients with 130 IMN metastases was mapped. The location was in the first 3 intercostal spaces in 102 of 130 nodal metastases (78%), whereas 18 of 130 IMNs (14%) were located caudal to the third intercostal space and 10 of 130 IMNs (8%) were located cranial to the first intercostal space. Of the 102 nodal metastases within the first 3 intercostal spaces, 54 (53%) were located within the Radiation Therapy Oncology Group consensus volume. Relative to the IM vessels, 19 nodal metastases (19%) were located medially with a mean distance of 2.2 mm (SD, 2.9 mm) whereas 29 (28%) were located laterally with a mean distance of 3.6 mm (SD, 2.5 mm). Ninety percent of lymph nodes within the first 3 intercostal spaces would have been encompassed within a 4-mm medial and lateral expansion on the IM vessels. Conclusions: In women with indications for elective IMN irradiation, a 4-mm medial and lateral expansion on the IM vessels may be appropriate. In women with known IMN involvement, cranial extension to the confluence of the IM vein with the brachiocephalic vein with or without caudal extension to the fourth or fifth interspace may be considered provided that normal tissue constraints are met.« less

  14. Target location after deep cerebral biopsies using low-volume air injection in 75 patients. Results and technical note.

    PubMed

    Poca, Maria A; Martínez-Ricarte, Francisco-Ramon; Gándara, Dario F; Coscojuela, Pilar; Martínez-Sáez, Elena; Sahuquillo, Juan

    2017-10-01

    Stereotactic biopsy is a minimally invasive technique that allows brain tissue samples to be obtained with low risk. Classically, different techniques have been used to identify the biopsy site after surgery. To describe a technique to identify the precise location of the target in the postoperative CT scan using the injection of a low volume of air into the biopsy cannula. Seventy-five biopsies were performed in 65 adults and 10 children (40 males and 35 females, median age 51 years). Frame-based biopsy was performed in 46 patients, while frameless biopsy was performed in the remaining 29 patients. In both systems, after brain specimens had been collected and with the biopsy needle tip in the center of the target, a small volume of air (median 0.7 cm 3 ) was injected into the site. A follow-up CT scan was performed in all patients. Intracranial air in the selected target was present in 69 patients (92%). No air was observed in two patients (air volume administered in these 2 cases was below 0.7 cm 3 ), while in the remaining four patients blood content was observed in the target. The diagnostic yield in this series was 97.3%. No complications were found to be associated with intracranial air injection in any of the 75 patients who underwent this procedure. The air-injection maneuver proposed for use in stereotactic biopsies of intracranial mass lesions is a safe and reliable technique that allows the exact biopsy site to be located without any related complications.

  15. Fast interactive real-time volume rendering of real-time three-dimensional echocardiography: an implementation for low-end computers

    NASA Technical Reports Server (NTRS)

    Saracino, G.; Greenberg, N. L.; Shiota, T.; Corsi, C.; Lamberti, C.; Thomas, J. D.

    2002-01-01

    Real-time three-dimensional echocardiography (RT3DE) is an innovative cardiac imaging modality. However, partly due to lack of user-friendly software, RT3DE has not been widely accepted as a clinical tool. The object of this study was to develop and implement a fast and interactive volume renderer of RT3DE datasets designed for a clinical environment where speed and simplicity are not secondary to accuracy. Thirty-six patients (20 regurgitation, 8 normal, 8 cardiomyopathy) were imaged using RT3DE. Using our newly developed software, all 3D data sets were rendered in real-time throughout the cardiac cycle and assessment of cardiac function and pathology was performed for each case. The real-time interactive volume visualization system is user friendly and instantly provides consistent and reliable 3D images without expensive workstations or dedicated hardware. We believe that this novel tool can be used clinically for dynamic visualization of cardiac anatomy.

  16. Effects of online cone-beam computed tomography with active breath control in determining planning target volume during accelerated partial breast irradiation.

    PubMed

    Li, Y; Zhong, R; Wang, X; Ai, P; Henderson, F; Chen, N; Luo, F

    2017-04-01

    To test if active breath control during cone-beam computed tomography (CBCT) could improve planning target volume during accelerated partial breast radiotherapy for breast cancer. Patients who were more than 40 years old, underwent breast-conserving dissection and planned for accelerated partial breast irradiation, and with postoperative staging limited to T1-2 N0 M0, or postoperative staging T2 lesion no larger than 3cm with a negative surgical margin greater than 2mm were enrolled. Patients with lobular carcinoma or extensive ductal carcinoma in situ were excluded. CBCT images were obtained pre-correction, post-correction and post-treatment. Set-up errors were recorded at left-right, anterior-posterior and superior-inferior directions. The differences between these CBCT images, as well as calculated radiation doses, were compared between patients with active breath control or free breathing. Forty patients were enrolled, among them 25 had active breath control. A total of 836 CBCT images were obtained for analysis. CBCT significantly reduced planning target volume. However, active breath control did not show significant benefit in decreasing planning target volume margin and the doses of organ-at-risk when compared to free breathing. CBCT, but not active breath control, could reduce planning target volume during accelerated partial breast irradiation. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  17. Synovial tissue volume: a treatment target in knee osteoarthritis (OA).

    PubMed

    O'Neill, Terence W; Parkes, Matthew J; Maricar, Nasimah; Marjanovic, Elizabeth J; Hodgson, Richard; Gait, Andrew D; Cootes, Timothy F; Hutchinson, Charles E; Felson, David T

    2016-01-01

    Synovitis occurring frequently in osteoarthritis (OA) may be a targeted outcome. There are no data examining whether synovitis changes following intra-articular intervention. Persons aged 40 years and older with painful knee OA participated in an open label trial of intra-articular steroid therapy. At all time points they completed the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire. They had a contrast-enhanced (CE) MRI immediately prior to an intra-articular steroid injection with a repeat scan within 20 days. Response status was assessed using the Osteoarthritis Research Society International (OARSI) response criteria. OARSI responders were followed until their pain relapsed either within 20% of baseline or 6 months, shortly after which a third MRI was performed. Synovial tissue volume (STV) was measured on postcontrast knee images. We looked at changes in the STV and in pain, and their association. 120 subjects with preinjection and postinjection CE MRI were followed. Their mean age was 62.3 years (SD=10.3) and 62 (52%) were women. The median time between injection and follow-up scan was 8 days (IQR 7-14 days). 85/120 (71%) were OARSI responders. Pain decreased (mean change in KOOS=+23.9; 95% CI 20.1 to 27.8, p<0.001) following steroid injection, as did mean STV (mean change=-1071 mm(3); 95% CI -1839 mm(3) to -303 mm(3), p=0.01). Of the 80 who returned for a third MRI, pain relapsed in 57, and in the 48 of those with MRI data, STV increased between follow-up and final visit (+1220 mm(3); 95% CI 25 mm(3) to 2414 mm(3), p=0.05). 23 were persistent responders at 6 months and, in these, STV did not increase (mean change=-202 mm(3); 95% CI -2008 mm(3) to 1604 mm(3), p=0.83). Controlling for variation over time, there was a significant association between synovitis volume and KOOS pain (b coefficient-change in KOOS pain score per 1000 mm(3) change in STV=-1.13; 95% CI -1.87 to -0.39, p=0.003), although STV accounted for only a small proportion of

  18. Fast and slow thinking in distressing delusions: A review of the literature and implications for targeted therapy.

    PubMed

    Ward, Thomas; Garety, Philippa A

    2017-09-16

    The recent literature on reasoning biases in psychosis and delusions is reviewed. The state-of-the-art knowledge from systematic reviews and meta-analyses on the evidence for jumping to conclusions is briefly summarised, before a fuller discussion of the more recent empirical literature on belief flexibility as applied to delusions. The methodology and evidence in relation to studies of belief flexibility and the Bias Against Disconfirmatory Evidence (BADE) across the delusional continuum will be critically appraised, and implications drawn for improving cognitive therapy. It will be proposed that dual process models of reasoning, which Kahneman (Kahneman, 2011) popularised as 'fast and slow thinking', provide a useful theoretical framework for integrating further research and informing clinical practice. The emergence of therapies which specifically target fast and slow thinking in people with distressing delusions will be described. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Speed-up of the volumetric method of moments for the approximate RCS of large arbitrary-shaped dielectric targets

    NASA Astrophysics Data System (ADS)

    Moreno, Javier; Somolinos, Álvaro; Romero, Gustavo; González, Iván; Cátedra, Felipe

    2017-08-01

    A method for the rigorous computation of the electromagnetic scattering of large dielectric volumes is presented. One goal is to simplify the analysis of large dielectric targets with translational symmetries taken advantage of their Toeplitz symmetry. Then, the matrix-fill stage of the Method of Moments is efficiently obtained because the number of coupling terms to compute is reduced. The Multilevel Fast Multipole Method is applied to solve the problem. Structured meshes are obtained efficiently to approximate the dielectric volumes. The regular mesh grid is achieved by using parallelepipeds whose centres have been identified as internal to the target. The ray casting algorithm is used to classify the parallelepiped centres. It may become a bottleneck when too many points are evaluated in volumes defined by parametric surfaces, so a hierarchical algorithm is proposed to minimize the number of evaluations. Measurements and analytical results are included for validation purposes.

  20. Potential implications of the bystander effect on TCP and EUD when considering target volume dose heterogeneity.

    PubMed

    Balderson, Michael J; Kirkby, Charles

    2015-01-01

    In light of in vitro evidence suggesting that radiation-induced bystander effects may enhance non-local cell killing, there is potential for impact on radiotherapy treatment planning paradigms such as the goal of delivering a uniform dose throughout the clinical target volume (CTV). This work applies a bystander effect model to calculate equivalent uniform dose (EUD) and tumor control probability (TCP) for external beam prostate treatment and compares the results with a more common model where local response is dictated exclusively by local absorbed dose. The broad assumptions applied in the bystander effect model are intended to place an upper limit on the extent of the results in a clinical context. EUD and TCP of a prostate cancer target volume under conditions of increasing dose heterogeneity were calculated using two models: One incorporating bystander effects derived from previously published in vitro bystander data ( McMahon et al. 2012 , 2013a); and one using a common linear-quadratic (LQ) response that relies exclusively on local absorbed dose. Dose through the CTV was modelled as a normal distribution, where the degree of heterogeneity was then dictated by changing the standard deviation (SD). Also, a representative clinical dose distribution was examined as cold (low dose) sub-volumes were systematically introduced. The bystander model suggests a moderate degree of dose heterogeneity throughout a target volume will yield as good or better outcome compared to a uniform dose in terms of EUD and TCP. For a typical intermediate risk prostate prescription of 78 Gy over 39 fractions maxima in EUD and TCP as a function of increasing SD occurred at SD ∼ 5 Gy. The plots only dropped below the uniform dose values for SD ∼ 10 Gy, almost 13% of the prescribed dose. Small, but potentially significant differences in the outcome metrics between the models were identified in the clinically-derived dose distribution as cold sub-volumes were introduced. In terms of

  1. On FAST3D simulations of directly-driven inertial-fusion targets with high-Z layers for reducing laser imprint and surface non-uniformity growth

    NASA Astrophysics Data System (ADS)

    Bates, Jason; Schmitt, Andrew; Klapisch, Marcel; Karasik, Max; Obenschain, Steve

    2013-10-01

    Modifications to the FAST3D code have been made to enhance its ability to simulate the dynamics of plastic ICF targets with high-Z overcoats. This class of problems is challenging computationally due in part to plasma conditions that are not in a state of local thermodynamic equilibrium and to the presence of mixed computational cells containing more than one material. Recently, new opacity tables for gold, palladium and plastic have been generated with an improved version of the STA code. These improved tables provide smoother, higher-fidelity opacity data over a wider range of temperature and density states than before, and contribute to a more accurate treatment of radiative transfer processes in FAST3D simulations. Furthermore, a new, more efficient subroutine known as ``MMEOS'' has been installed in the FAST3D code for determining pressure and temperature equilibrium conditions within cells containing multiple materials. We will discuss these topics, and present new simulation results for high-Z planar-target experiments performed recently on the NIKE Laser Facility. Work supported by DOE/NNSA.

  2. Volume comparison of radiofrequency ablation at 3- and 5-cm target volumes for four different radiofrequency generators: MR volumetry in an open 1-T MRI system versus macroscopic measurement.

    PubMed

    Rathke, Hendrik; Hamm, Bernd; Guettler, Felix; Lohneis, Philipp; Stroux, Andrea; Suttmeyer, Britta; Jonczyk, Martin; Teichgräber, Ulf; de Bucourt, Maximilian

    2015-12-01

    In a patient, it is usually not macroscopically possible to estimate the non-viable volume induced by radiofrequency ablation (RFA) after the procedure. The purpose of this study was to use an ex vivo bovine liver model to perform magnetic resonance (MR) volumetry of the visible tissue signal change induced by RFA and to correlate the MR measurement with the actual macroscopic volume measured in the dissected specimens. Sixty-four liver specimens cut from 16 bovine livers were ablated under constant simulated, close physiological conditions with target volumes set to 14.14 ml (3-cm lesion) and 65.45 ml (5-cm lesion). Four commercially available radiofrequency (RF) systems were tested (n=16 for each system; n=8 for 3 cm and n=8 for 5 cm). A T1-weighted turbo spin echo (TSE) sequence with inversion recovery and a proton-density (PD)-weighted TSE sequence were acquired in a 1.0-T open magnetic resonance imaging (MRI) system. After manual dissection, actual macroscopic ablation diameters were measured and volumes calculated. MR volumetry was performed using a semiautomatic software tool. To validate the correctness and feasibility of the volume formula in macroscopic measurements, MR multiplanar reformation diameter measurements with subsequent volume calculation and semiautomatic MR volumes were correlated. Semiautomatic MR volumetry yielded smaller volumes than manual measurement after dissection, irrespective of RF system used, target lesion size, and MR sequence. For the 3-cm lesion, only 43.3% (T1) and 41.5% (PD) of the entire necrosis are detectable. For the 5-cm lesion, only 40.8% (T1) and 37.2% (PD) are visualized in MRI directly after intervention. The correlation between semiautomatic MR volumes and calculated MR volumes was 0.888 for the T1-weighted sequence and 0.875 for the PD sequence. After correlation of semiautomatic MR volumes and calculated MR volumes, it seems reasonable to use the respective volume formula for macroscopic volume calculation

  3. Sparse PDF Volumes for Consistent Multi-Resolution Volume Rendering.

    PubMed

    Sicat, Ronell; Krüger, Jens; Möller, Torsten; Hadwiger, Markus

    2014-12-01

    This paper presents a new multi-resolution volume representation called sparse pdf volumes, which enables consistent multi-resolution volume rendering based on probability density functions (pdfs) of voxel neighborhoods. These pdfs are defined in the 4D domain jointly comprising the 3D volume and its 1D intensity range. Crucially, the computation of sparse pdf volumes exploits data coherence in 4D, resulting in a sparse representation with surprisingly low storage requirements. At run time, we dynamically apply transfer functions to the pdfs using simple and fast convolutions. Whereas standard low-pass filtering and down-sampling incur visible differences between resolution levels, the use of pdfs facilitates consistent results independent of the resolution level used. We describe the efficient out-of-core computation of large-scale sparse pdf volumes, using a novel iterative simplification procedure of a mixture of 4D Gaussians. Finally, our data structure is optimized to facilitate interactive multi-resolution volume rendering on GPUs.

  4. Sparse PDF Volumes for Consistent Multi-Resolution Volume Rendering

    PubMed Central

    Sicat, Ronell; Krüger, Jens; Möller, Torsten; Hadwiger, Markus

    2015-01-01

    This paper presents a new multi-resolution volume representation called sparse pdf volumes, which enables consistent multi-resolution volume rendering based on probability density functions (pdfs) of voxel neighborhoods. These pdfs are defined in the 4D domain jointly comprising the 3D volume and its 1D intensity range. Crucially, the computation of sparse pdf volumes exploits data coherence in 4D, resulting in a sparse representation with surprisingly low storage requirements. At run time, we dynamically apply transfer functions to the pdfs using simple and fast convolutions. Whereas standard low-pass filtering and down-sampling incur visible differences between resolution levels, the use of pdfs facilitates consistent results independent of the resolution level used. We describe the efficient out-of-core computation of large-scale sparse pdf volumes, using a novel iterative simplification procedure of a mixture of 4D Gaussians. Finally, our data structure is optimized to facilitate interactive multi-resolution volume rendering on GPUs. PMID:26146475

  5. Reliability of Serum Metabolites over a Two-Year Period: A Targeted Metabolomic Approach in Fasting and Non-Fasting Samples from EPIC

    PubMed Central

    Achaintre, David; Sacerdote, Carlotta; Vineis, Paolo; Key, Timothy J.; Onland Moret, N. Charlotte; Scalbert, Augustin; Rinaldi, Sabina; Ferrari, Pietro

    2015-01-01

    Objective Although metabolic profiles have been associated with chronic disease risk, lack of temporal stability of metabolite levels could limit their use in epidemiological investigations. The present study aims to evaluate the reliability over a two-year period of 158 metabolites and compare reliability over time in fasting and non-fasting serum samples. Methods Metabolites were measured with the AbsolueIDQp180 kit (Biocrates, Innsbruck, Austria) by mass spectrometry and included acylcarnitines, amino acids, biogenic amines, hexoses, phosphatidylcholines and sphingomyelins. Measurements were performed on repeat serum samples collected two years apart in 27 fasting men from Turin, Italy, and 39 non-fasting women from Utrecht, The Netherlands, all participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Reproducibility was assessed by estimating intraclass correlation coefficients (ICCs) in multivariable mixed models. Results In fasting samples, a median ICC of 0.70 was observed. ICC values were <0.50 for 48% of amino acids, 27% of acylcarnitines, 18% of lysophosphatidylcholines and 4% of phosphatidylcholines. In non-fasting samples, the median ICC was 0.54. ICC values were <0.50 for 71% of acylcarnitines, 48% of amino acids, 44% of biogenic amines, 36% of sphingomyelins, 34% of phosphatidylcholines and 33% of lysophosphatidylcholines. Overall, reproducibility was lower in non-fasting as compared to fasting samples, with a statistically significant difference for 19–36% of acylcarnitines, phosphatidylcholines and sphingomyelins. Conclusion A single measurement per individual may be sufficient for the study of 73% and 52% of the metabolites showing ICCs >0.50 in fasting and non-fasting samples, respectively. ICCs were higher in fasting samples that are preferable to non-fasting. PMID:26274920

  6. International guideline for the delineation of the clinical target volumes (CTV) for nasopharyngeal carcinoma.

    PubMed

    Lee, Anne W; Ng, Wai Tong; Pan, Jian Ji; Poh, Sharon S; Ahn, Yong Chan; AlHussain, Hussain; Corry, June; Grau, Cai; Grégoire, Vincent; Harrington, Kevin J; Hu, Chao Su; Kwong, Dora L; Langendijk, Johannes A; Le, Quynh Thu; Lee, Nancy Y; Lin, Jin Ching; Lu, Tai Xiang; Mendenhall, William M; O'Sullivan, Brian; Ozyar, Enis; Peters, Lester J; Rosenthal, David I; Soong, Yoke Lim; Tao, Yungan; Yom, Sue S; Wee, Joseph T

    2018-01-01

    Target delineation in nasopharyngeal carcinoma (NPC) often proves challenging because of the notoriously narrow therapeutic margin. High doses are needed to achieve optimal levels of tumour control, and dosimetric inadequacy remains one of the most important independent factors affecting treatment outcome. A review of the available literature addressing the natural behaviour of NPC and correlation between clinical and pathological aspects of the disease was conducted. Existing international guidelines as well as published protocols specified by clinical trials on contouring of clinical target volumes (CTV) were compared. This information was then summarized into a preliminary draft guideline which was then circulated to international experts in the field for exchange of opinions and subsequent voting on areas with the greatest controversies. Common areas of uncertainty and variation in practices among experts experienced in radiation therapy for NPC were elucidated. Iterative revisions were made based on extensive discussion and final voting on controversial areas by the expert panel, to formulate the recommendations on contouring of CTV based on optimal geometric expansion and anatomical editing for those structures with substantial risk of microscopic infiltration. Through this comprehensive review of available evidence and best practices at major institutions, as well as interactive exchange of vast experience by international experts, this set of consensus guidelines has been developed to provide a practical reference for appropriate contouring to ensure optimal target coverage. However, the final decision on the treatment volumes should be based on full consideration of individual patients' factors and facilities of an individual centre (including the quality of imaging methods and the precision of treatment delivery). Copyright © 2017 Elsevier B.V. All rights reserved.

  7. FDG-PET-based differential uptake volume histograms: a possible approach towards definition of biological target volumes.

    PubMed

    Devic, Slobodan; Mohammed, Huriyyah; Tomic, Nada; Aldelaijan, Saad; De Blois, François; Seuntjens, Jan; Lehnert, Shirley; Faria, Sergio

    2016-06-01

    Integration of fluorine-18 fludeoxyglucose ((18)F-FDG)-positron emission tomography (PET) functional data into conventional anatomically based gross tumour volume delineation may lead to optimization of dose to biological target volumes (BTV) in radiotherapy. We describe a method for defining tumour subvolumes using (18)F-FDG-PET data, based on the decomposition of differential uptake volume histograms (dUVHs). For 27 patients with histopathologically proven non-small-cell lung carcinoma (NSCLC), background uptake values were sampled within the healthy lung contralateral to a tumour in those image slices containing tumour and then scaled by the ratio of mass densities between the healthy lung and tumour. Signal-to-background (S/B) uptake values within volumes of interest encompassing the tumour were used to reconstruct the dUVHs. These were subsequently decomposed into the minimum number of analytical functions (in the form of differential uptake values as a function of S/B) that yielded acceptable net fits, as assessed by χ(2) values. Six subvolumes consistently emerged from the fitted dUVHs over the sampled volume of interest on PET images. Based on the assumption that each function used to decompose the dUVH may correspond to a single subvolume, the intersection between the two adjacent functions could be interpreted as a threshold value that differentiates them. Assuming that the first two subvolumes spread over the tumour boundary, we concentrated on four subvolumes with the highest uptake values, and their S/B thresholds [mean ± standard deviation (SD)] were 2.88 ± 0.98, 4.05 ± 1.55, 5.48 ± 2.06 and 7.34 ± 2.89 for adenocarcinoma, 3.01 ± 0.71, 4.40 ± 0.91, 5.99 ± 1.31 and 8.17 ± 2.42 for large-cell carcinoma and 4.54 ± 2.11, 6.46 ± 2.43, 8.87 ± 5.37 and 12.11 ± 7.28 for squamous cell carcinoma, respectively. (18)F-FDG-based PET data may potentially be used to identify BTV within the tumour in

  8. Target-locking acquisition with real-time confocal (TARC) microscopy.

    PubMed

    Lu, Peter J; Sims, Peter A; Oki, Hidekazu; Macarthur, James B; Weitz, David A

    2007-07-09

    We present a real-time target-locking confocal microscope that follows an object moving along an arbitrary path, even as it simultaneously changes its shape, size and orientation. This Target-locking Acquisition with Realtime Confocal (TARC) microscopy system integrates fast image processing and rapid image acquisition using a Nipkow spinning-disk confocal microscope. The system acquires a 3D stack of images, performs a full structural analysis to locate a feature of interest, moves the sample in response, and then collects the next 3D image stack. In this way, data collection is dynamically adjusted to keep a moving object centered in the field of view. We demonstrate the system's capabilities by target-locking freely-diffusing clusters of attractive colloidal particles, and activelytransported quantum dots (QDs) endocytosed into live cells free to move in three dimensions, for several hours. During this time, both the colloidal clusters and live cells move distances several times the length of the imaging volume.

  9. High-Frequency Jet Ventilation for Complete Target Immobilization and Reduction of Planning Target Volume in Stereotactic High Single-Dose Irradiation of Stage I Non-Small Cell Lung Cancer and Lung Metastases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fritz, Peter, E-mail: p.h.fritz@t-online.d; Kraus, Hans-Joerg; Muehlnickel, Werner

    2010-09-01

    Purpose: To demonstrate the feasibility of complete target immobilization by means of high-frequency jet ventilation (HFJV); and to show that the saving of planning target volume (PTV) on the stereotactic body radiation therapy (SBRT) under HFJV, compared with SBRT with respiratory motion, can be predicted with reliable accuracy by computed tomography (CT) scans at peak inspiration phase. Methods and Materials: A comparison regarding different methods for defining the PTV was carried out in 22 patients with tumors that clearly moved with respiration. A movement span of the gross tumor volume (GTV) was defined by fusing respiration-correlated CT scans. The PTVmore » enclosed the GTV positions with a safety margin throughout the breathing cycle. To create a PTV from CT scans acquired under HFJV, the same margins were drawn around the immobilized target. In addition, peak inspiration phase CT images (PIP-CTs) were used to approximate a target immobilized by HFJV. Results: The resulting HFJV-PTVs were between 11.6% and 45.4% smaller than the baseline values calculated as respiration-correlated CT-PTVs (median volume reduction, 25.4%). Tentative planning by means of PIP-CT PTVs predicted that in 19 of 22 patients, use of HFJV would lead to a reduction in volume of {>=}20%. Using this threshold yielded a positive predictive value of 0.89, as well as a sensitivity of 0.94 and a specificity of 0.5. Conclusions: In all patients, SBRT under HFJV provided a reliable immobilization of the GTVs and achieved a reduction in PTVs, regardless of patient compliance. Tentative planning facilitated the selection of patients who could better undergo radiation in respiratory standstill, both with greater accuracy and lung protection.« less

  10. Utilization of cone-beam CT for offline evaluation of target volume coverage during prostate image-guided radiotherapy based on bony anatomy alignment.

    PubMed

    Paluska, Petr; Hanus, Josef; Sefrova, Jana; Rouskova, Lucie; Grepl, Jakub; Jansa, Jan; Kasaova, Linda; Hodek, Miroslav; Zouhar, Milan; Vosmik, Milan; Petera, Jiri

    2012-01-01

    To assess target volume coverage during prostate image-guided radiotherapy based on bony anatomy alignment and to assess possibility of safety margin reduction. Implementation of IGRT should influence safety margins. Utilization of cone-beam CT provides current 3D anatomic information directly in irradiation position. Such information enables reconstruction of the actual dose distribution. Seventeen prostate patients were treated with daily bony anatomy image-guidance. Cone-beam CT (CBCT) scans were acquired once a week immediately after bony anatomy alignment. After the prostate, seminal vesicles, rectum and bladder were contoured, the delivered dose distribution was reconstructed. Target dose coverage was evaluated by the proportion of the CTV encompassed by the 95% isodose. Original plans employed a 1 cm safety margin. Alternative plans assuming a smaller 7 mm margin between CTV and PTV were evaluated in the same way. Rectal and bladder volumes were compared with the initial ones. Rectal and bladder volumes irradiated with doses higher than 75 Gy, 70 Gy, 60 Gy, 50 Gy and 40 Gy were analyzed. In 12% of reconstructed plans the prostate coverage was not sufficient. The prostate underdosage was observed in 5 patients. Coverage of seminal vesicles was not satisfactory in 3% of plans. Most of the target underdosage corresponded to excessive rectal or bladder filling. Evaluation of alternative plans assuming a smaller 7 mm margin revealed 22% and 11% of plans where prostate and seminal vesicles coverage, respectively, was compromised. These were distributed over 8 and 7 patients, respectively. Sufficient dose coverage of target volumes was not achieved for all patients. Reducing of safety margin is not acceptable. Initial rectal and bladder volumes cannot be considered representative for subsequent treatment.

  11. Long-term Outcomes of Temporal Hollowing Augmentation by Targeted Volume Restoration of Fat Compartments in Chinese Adults.

    PubMed

    Huang, Ru-Lin; Xie, Yun; Wang, Wenjin; Tan, Pohching; Li, Qingfeng

    2018-04-19

    Previous anatomical and clinical studies have suggested that targeted restoration of the volume and distribution of fat compartments using appropriate cannula entry sites and injection planes is an excellent fat-grafting technique for facial contouring and hand rejuvenation. To perform subjective and objective evaluations of the safe and effective profile of the targeted fat-grafting technique for temporal hollowing augmentation. In a retrospective cohort study, a total of 96 consecutive patients with temporal hollowing were treated at the Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai, China, with the targeted fat-grafting technique from January 1, 2009, to January 1, 2017. The safety and efficacy profile of this technique was evaluated by the following methods: (1) a quantitative measurement of fat-graft survival and temporal augmentation rates by using 3-dimensional laser scanning, (2) a subjective assessment using a satisfaction survey and the Hollowness Severity Rating Scale (grades range from 0-3, with higher grades representing more hollowness), and (3) the complication rate. Of the 96 study patients, 94 (97.9%) were women and the mean (SD) age was 34.4 (7.4) years. Of the 142 autologous fat-grafting procedures performed, the mean (SD) total follow-up time was 16.3 (3.2) months, with a mean (SD) of 1.5 (0.7) procedures performed. The mean (SD) baseline volume requirement per temple for each patient was 12.8 (4.8) mL, and the total volume of the fat graft per temple was 17.8 (7.5) mL. Quantitative analysis revealed that the mean (SD) total augmentation volume per temple was 11.7 (3.0) mL, the total survival rate of the fat grafts was 65.7% (12.6%), and total augmentation rate of hollowness was 91.4% (23.4%). Subjective analysis revealed that all patients showed an improved appearance after fat grafting, and 142 temples (74.0%) exhibited clinical improvement by more than 2 grades. In all, 88 patients (91.7%) were

  12. Polarization of fast particle beams by collisional pumping

    DOEpatents

    Stearns, J. Warren; Kaplan, Selig N.; Pyle, Robert V.; Anderson, L. Wilmer; Ruby, Lawrence; Schlachter, Alfred S.

    1988-01-01

    Method and apparatus for highly polarizing a fast beam of particles by collisional pumping, including generating a fast beam of particles, and also generating a thick electron-spin-polarized medium positioned as a target for the beam. The target is made sufficiently thick to allow the beam to interact with the medium to produce collisional pumping whereby the beam becomes highly polarized.

  13. Retroperitoneal Sarcoma Target Volume and Organ at Risk Contour Delineation Agreement Among NRG Sarcoma Radiation Oncologists

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baldini, Elizabeth H., E-mail: ebaldini@partners.org; Abrams, Ross A.; Bosch, Walter

    Purpose: The purpose of this study was to evaluate the variability in target volume and organ at risk (OAR) contour delineation for retroperitoneal sarcoma (RPS) among 12 sarcoma radiation oncologists. Methods and Materials: Radiation planning computed tomography (CT) scans for 2 cases of RPS were distributed among 12 sarcoma radiation oncologists with instructions for contouring gross tumor volume (GTV), clinical target volume (CTV), high-risk CTV (HR CTV: area judged to be at high risk of resulting in positive margins after resection), and OARs: bowel bag, small bowel, colon, stomach, and duodenum. Analysis of contour agreement was performed using the simultaneousmore » truth and performance level estimation (STAPLE) algorithm and kappa statistics. Results: Ten radiation oncologists contoured both RPS cases, 1 contoured only RPS1, and 1 contoured only RPS2 such that each case was contoured by 11 radiation oncologists. The first case (RPS 1) was a patient with a de-differentiated (DD) liposarcoma (LPS) with a predominant well-differentiated (WD) component, and the second case (RPS 2) was a patient with DD LPS made up almost entirely of a DD component. Contouring agreement for GTV and CTV contours was high. However, the agreement for HR CTVs was only moderate. For OARs, agreement for stomach, bowel bag, small bowel, and colon was high, but agreement for duodenum (distorted by tumor in one of these cases) was fair to moderate. Conclusions: For preoperative treatment of RPS, sarcoma radiation oncologists contoured GTV, CTV, and most OARs with a high level of agreement. HR CTV contours were more variable. Further clarification of this volume with the help of sarcoma surgical oncologists is necessary to reach consensus. More attention to delineation of the duodenum is also needed.« less

  14. Retroperitoneal Sarcoma Target Volume and Organ at Risk Contour Delineation Agreement Among NRG Sarcoma Radiation Oncologists

    PubMed Central

    Baldini, Elizabeth H.; Abrams, Ross A.; Bosch, Walter; Roberge, David; Haas, Rick L.M.; Catton, Charles N.; Indelicato, Daniel J.; Olsen, Jeffrey R.; Deville, Curtiland; Chen, Yen-Lin; Finkelstein, Steven E.; DeLaney, Thomas F.; Wang, Dian

    2015-01-01

    Purpose The purpose of this study was to evaluate the variability in target volume and organ at risk (OAR) contour delineation for retroperitoneal sarcoma (RPS) among 12 sarcoma radiation oncologists. Methods and Materials Radiation planning computed tomography (CT) scans for 2 cases of RPS were distributed among 12 sarcoma radiation oncologists with instructions for contouring gross tumor volume (GTV), clinical target volume (CTV), high-risk CTV (HR CTV: area judged to be at high risk of resulting in positive margins after resection), and OARs: bowel bag, small bowel, colon, stomach, and duodenum. Analysis of contour agreement was performed using the simultaneous truth and performance level estimation (STAPLE) algorithm and kappa statistics. Results Ten radiation oncologists contoured both RPS cases, 1 contoured only RPS1, and 1 contoured only RPS2 such that each case was contoured by 11 radiation oncologists. The first case (RPS 1) was a patient with a de-differentiated (DD) liposarcoma (LPS) with a predominant well-differentiated (WD) component, and the second case (RPS 2) was a patient with DD LPS made up almost entirely of a DD component. Contouring agreement for GTV and CTV contours was high. However, the agreement for HR CTVs was only moderate. For OARs, agreement for stomach, bowel bag, small bowel, and colon was high, but agreement for duodenum (distorted by tumor in one of these cases) was fair to moderate. Conclusions For preoperative treatment of RPS, sarcoma radiation oncologists contoured GTV, CTV, and most OARs with a high level of agreement. HR CTV contours were more variable. Further clarification of this volume with the help of sarcoma surgical oncologists is necessary to reach consensus. More attention to delineation of the duodenum is also needed. PMID:26194680

  15. Heating a plasma by a broadband stream of fast electrons: Fast ignition, shock ignition, and Gbar shock wave applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gus’kov, S. Yu., E-mail: guskov@sci.lebedev.ru; Nicolai, Ph.; Ribeyre, X.

    2015-09-15

    An exact analytic solution is found for the steady-state distribution function of fast electrons with an arbitrary initial spectrum irradiating a planar low-Z plasma with an arbitrary density distribution. The solution is applied to study the heating of a material by fast electrons of different spectra such as a monoenergetic spectrum, a step-like distribution in a given energy range, and a Maxwellian spectrum, which is inherent in laser-produced fast electrons. The heating of shock- and fast-ignited precompressed inertial confinement fusion (ICF) targets as well as the heating of a target designed to generate a Gbar shock wave for equation ofmore » state (EOS) experiments by laser-produced fast electrons with a Maxwellian spectrum is investigated. A relation is established between the energies of two groups of Maxwellian fast electrons, which are responsible for generation of a shock wave and heating the upstream material (preheating). The minimum energy of the fast and shock igniting beams as well as of the beam for a Gbar shock wave generation increases with the spectral width of the electron distribution.« less

  16. Metabolic effects of large-volume liposuction for obese healthy women: a meta-analysis of fasting insulin levels.

    PubMed

    Boriani, Filippo; Villani, Riccardo; Morselli, Paolo Giovanni

    2014-10-01

    Obesity is increasingly frequent in our society and is associated closely with metabolic disorders. As some studies have suggested, removal of fat tissue through liposuction and dermolipectomies may be of some benefit in the improvement of metabolic indices. This article aimed to review the published literature on this topic and to evaluate metabolic variations meta-analytically after liposuction, dermolipectomy, or both. Through a literature search with the PubMed/Medline database, 14 studies were identified. All articles were analyzed, and several metabolic variables were chosen in the attempt to meta-analyze the effect of adipose tissue removal through the various studies. All statistical calculations were performed with Review Manager (RevMan), version 5.0. Several cardiovascular and metabolic variables are described as prone to variations after body-contouring procedures when a significant amount of adipose tissue has been excised. Four of the studies included in the analysis reported improvements in all the parameters examined. Seven articles showed improvement in some variables and no improvement in others, whereas three studies showed no beneficial variation in any of the considered indicators after body-contouring procedures. Fasting plasma insulin was identified as the only variable for which a meta-analysis of five included studies was possible. The meta-analysis showed a statistically significant reduction in fasting plasma insulin resulting from large-volume liposuction in obese healthy women. Many beneficial metabolic effects resulting from dermolipectomy and liposuction procedures are described in the literature. In particular, fasting plasma insulin and thus insulin sensitivity seem to be positively influenced. Further research, including prospective clinical studies, is necessary for better exploration of the effects that body-contouring plastic surgery procedures have on metabolic parameters.

  17. Potential dosimetric benefits of adaptive tumor tracking over the internal target volume concept for stereotactic body radiation therapy of pancreatic cancer.

    PubMed

    Karava, Konstantina; Ehrbar, Stefanie; Riesterer, Oliver; Roesch, Johannes; Glatz, Stefan; Klöck, Stephan; Guckenberger, Matthias; Tanadini-Lang, Stephanie

    2017-11-09

    Radiotherapy for pancreatic cancer has two major challenges: (I) the tumor is adjacent to several critical organs and, (II) the mobility of both, the tumor and its surrounding organs at risk (OARs). A treatment planning study simulating stereotactic body radiation therapy (SBRT) for pancreatic tumors with both the internal target volume (ITV) concept and the tumor tracking approach was performed. The two respiratory motion-management techniques were compared in terms of doses to the target volume and organs at risk. Two volumetric-modulated arc therapy (VMAT) treatment plans (5 × 5 Gy) were created for each of the 12 previously treated pancreatic cancer patients, one using the ITV concept and one the tumor tracking approach. To better evaluate the overall dose delivered to the moving tumor volume, 4D dose calculations were performed on four-dimensional computed tomography (4DCT) scans. The resulting planning target volume (PTV) size for each technique was analyzed. Target and OAR dose parameters were reported and analyzed for both 3D and 4D dose calculation. Tumor motion ranged from 1.3 to 11.2 mm. Tracking led to a reduction of PTV size (max. 39.2%) accompanied with significant better tumor coverage (p<0.05, paired Wilcoxon signed rank test) both in 3D and 4D dose calculations and improved organ at risk sparing. Especially for duodenum, stomach and liver, the mean dose was significantly reduced (p<0.05) with tracking for 3D and 4D dose calculations. By using an adaptive tumor tracking approach for respiratory-induced pancreatic motion management, a significant reduction in PTV size can be achieved, which subsequently facilitates treatment planning, and improves organ dose sparing. The dosimetric benefit of tumor tracking is organ and patient-specific.

  18. A new functional method to choose the target lobe for lung volume reduction in emphysema - comparison with the conventional densitometric method.

    PubMed

    Hetzel, Juergen; Boeckeler, Michael; Horger, Marius; Ehab, Ahmed; Kloth, Christopher; Wagner, Robert; Freitag, Lutz; Slebos, Dirk-Jan; Lewis, Richard Alexander; Haentschel, Maik

    2017-01-01

    Lung volume reduction (LVR) improves breathing mechanics by reducing hyperinflation. Lobar selection usually focuses on choosing the most destroyed emphysematous lobes as seen on an inspiratory CT scan. However, it has never been shown to what extent these densitometric CT parameters predict the least deflation of an individual lobe during expiration. The addition of expiratory CT analysis allows measurement of the extent of lobar air trapping and could therefore provide additional functional information for choice of potential treatment targets. To determine lobar vital capacity/lobar total capacity (LVC/LTC) as a functional parameter for lobar air trapping using on an inspiratory and expiratory CT scan. To compare lobar selection by LVC/LTC with the established morphological CT density parameters. 36 patients referred for endoscopic LVR were studied. LVC/LTC, defined as delta volume over maximum volume of a lobe, was calculated using inspiratory and expiratory CT scans. The CT morphological parameters of mean lung density (MLD), low attenuation volume (LAV), and 15th percentile of Hounsfield units (15%P) were determined on an inspiratory CT scan for each lobe. We compared and correlated LVC/LTC with MLD, LAV, and 15%P. There was a weak correlation between the functional parameter LVC/LTC and all inspiratory densitometric parameters. Target lobe selection using lowest lobar deflation (lowest LVC/LTC) correlated with target lobe selection based on lowest MLD in 18 patients (50.0%), with the highest LAV in 13 patients (36.1%), and with the lowest 15%P in 12 patients (33.3%). CT-based measurement of deflation (LVC/LTC) as a functional parameter correlates weakly with all densitometric CT parameters on a lobar level. Therefore, morphological criteria based on inspiratory CT densitometry partially reflect the deflation of particular lung lobes, and may be of limited value as a sole predictor for target lobe selection in LVR.

  19. FastMag: Fast micromagnetic simulator for complex magnetic structures (invited)

    NASA Astrophysics Data System (ADS)

    Chang, R.; Li, S.; Lubarda, M. V.; Livshitz, B.; Lomakin, V.

    2011-04-01

    A fast micromagnetic simulator (FastMag) for general problems is presented. FastMag solves the Landau-Lifshitz-Gilbert equation and can handle multiscale problems with a high computational efficiency. The simulator derives its high performance from efficient methods for evaluating the effective field and from implementations on massively parallel graphics processing unit (GPU) architectures. FastMag discretizes the computational domain into tetrahedral elements and therefore is highly flexible for general problems. The magnetostatic field is computed via the superposition principle for both volume and surface parts of the computational domain. This is accomplished by implementing efficient quadrature rules and analytical integration for overlapping elements in which the integral kernel is singular. Thus, discretized superposition integrals are computed using a nonuniform grid interpolation method, which evaluates the field from N sources at N collocated observers in O(N) operations. This approach allows handling objects of arbitrary shape, allows easily calculating of the field outside the magnetized domains, does not require solving a linear system of equations, and requires little memory. FastMag is implemented on GPUs with ?> GPU-central processing unit speed-ups of 2 orders of magnitude. Simulations are shown of a large array of magnetic dots and a recording head fully discretized down to the exchange length, with over a hundred million tetrahedral elements on an inexpensive desktop computer.

  20. SU-E-T-287: Dose Verification On the Variation of Target Volume and Organ at Risk in Preradiation Chemotherapy IMRT for Nasopharyngeal Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, X; Kong, L; Wang, J

    2015-06-15

    Purpose: To quantify the target volume and organ at risk of nasopharyngeal carcinoma (NPC) patients with preradiation chemotherapy based on CT scanned during intensity-modulated radiotherapy (IMRT), and recalculate the dose distribution. Methods: Seven patients with NPC and preradiation chemotherapy, treated with IMRT (35 to 37 fractions) were reviewed. Repeat CT scanning was required to all of the patients during the radiotherapy, and the number of repeat CTs varies from 2 to 6. The plan CT and repeat CT were generated by different CT scanner. To ensure crespectively on the same IMPT plan. The real dose distribution was calculated by deformablemore » registration and weighted method in Raystation (v 4.5.1). The fraction of each dose is based on radiotherapy record. The volumetric and dose differences among these images were calculated for nascIpharyngeal tumor and retro-pharyngeal lymph nodes (GTV-NX), neck lymph nodes(GTV-ND), and parotid glands. Results: The volume variation in GTV-NX from CT1 to CT2 was 1.15±3.79%, and in GTV-LN −0.23±4.93%. The volume variation in left parotid from CT1 to CT2 was −6.79±11.91%, and in right parotid −3.92±8.80%. In patient 2, the left parotid volume were decreased remarkably, as a Result, the V30 and V40 of it were increased as well. Conclusion: The target volume of patients with NPC varied lightly during IMRT. It shows that preradiation chemotherapy can control the target volume variation and perform a good dose repeatability. Also, the decreasing volume of parotid in some patient might increase the dose of it, which might course potential complications.« less

  1. The potential advantages of (18)FDG PET/CT-based target volume delineation in radiotherapy planning of head and neck cancer.

    PubMed

    Moule, Russell N; Kayani, Irfan; Moinuddin, Syed A; Meer, Khalda; Lemon, Catherine; Goodchild, Kathleen; Saunders, Michele I

    2010-11-01

    This study investigated two fixed threshold methods to delineate the target volume using (18)FDG PET/CT before and during a course of radical radiotherapy in locally advanced squamous cell carcinoma of the head and neck. Patients were enrolled into the study between March 2006 and May 2008. (18)FDG PET/CT scans were carried out 72h prior to the start of radiotherapy and then at 10, 44 and 66Gy. Functional volumes were delineated according to the SUV Cut Off (SUVCO) (2.5, 3.0, 3.5, and 4.0bwg/ml) and percentage of the SUVmax (30%, 35%, 40%, 45%, and 50%) thresholds. The background (18)FDG uptake and the SUVmax within the volumes were also assessed. Primary and lymph node volumes for the eight patients significantly reduced with each increase in the delineation threshold (for example 2.5-3.0bwg/ml SUVCO) compared to the baseline threshold at each imaging point. There was a significant reduction in the volume (p⩽0.0001-0.01) after 36Gy compared to the 0Gy by the SUVCO method. There was a negative correlation between the SUVmax within the primary and lymph node volumes and delivered radiation dose (p⩽0.0001-0.011) but no difference in the SUV within the background reference region. The volumes delineated by the PTSUVmax method increased with the increase in the delivered radiation dose after 36Gy because the SUVmax within the region of interest used to define the edge of the volume was equal or less than the background (18)FDG uptake and the software was unable to effectively differentiate between tumour and background uptake. The changes in the target volumes delineated by the SUVCO method were less susceptible to background (18)FDG uptake compared to those delineated by the PTSUVmax and may be more helpful in radiotherapy planning. The best method and threshold have still to be determined within institutions, both nationally and internationally. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  2. Cytoplasm-to-myonucleus ratios and succinate dehydrogenase activities in adult rat slow and fast muscle fibers

    NASA Technical Reports Server (NTRS)

    Tseng, B. S.; Kasper, C. E.; Edgerton, V. R.

    1994-01-01

    The relationship between myonuclear number, cellular size, succinate dehydrogenase activity, and myosin type was examined in single fiber segments (n = 54; 9 +/- 3 mm long) mechanically dissected from soleus and plantaris muscles of adult rats. One end of each fiber segment was stained for DNA before quantitative photometric analysis of succinate dehydrogenase activity; the other end was double immunolabeled with fast and slow myosin heavy chain monoclonal antibodies. Mean +/- S.D. cytoplasmic volume/myonucleus ratio was higher in fast and slow plantaris fibers (112 +/- 69 vs. 34 +/- 21 x 10(3) microns3) than fast and slow soleus fibers (40 +/- 20 vs. 30 +/- 14 x 10(3) microns3), respectively. Slow fibers always had small volumes/myonucleus, regardless of fiber diameter, succinate dehydrogenase activity, or muscle of origin. In contrast, smaller diameter (< 70 microns) fast soleus and plantaris fibers with high succinate dehydrogenase activity appeared to have low volumes/myonucleus while larger diameter (> 70 microns) fast fibers with low succinate dehydrogenase activity always had large volume/myonucleus. Slow soleus fibers had significantly greater numbers of myonuclei/mm than did either fast soleus or fast plantaris fibers (116 +/- 51 vs. 55 +/- 22 and 44 +/- 23), respectively. These data suggest that the myonuclear domain is more limited in slow than fast fibers and in the fibers with a high, compared to a low, oxidative metabolic capability.

  3. Dosimetric Advantages of Midventilation Compared With Internal Target Volume for Radiation Therapy of Pancreatic Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lens, Eelco, E-mail: e.lens@amc.uva.nl; Horst, Astrid van der; Versteijne, Eva

    2015-07-01

    Purpose: The midventilation (midV) approach can be used to take respiratory-induced pancreatic tumor motion into account during radiation therapy. In this study, the dosimetric consequences for organs at risk and tumor coverage of using a midV approach compared with using an internal target volume (ITV) were investigated. Methods and Materials: For each of the 18 patients, 2 treatment plans (25 × 2.0 Gy) were created, 1 using an ITV and 1 using a midV approach. The midV dose distribution was blurred using the respiratory-induced motion from 4-dimensional computed tomography. The resulting planning target volume (PTV) coverage for this blurred dosemore » distribution was analyzed; PTV coverage was required to be at least V{sub 95%} >98%. In addition, the change in PTV size and the changes in V{sub 10Gy}, V{sub 20Gy}, V{sub 30Gy}, V{sub 40Gy}, D{sub mean} and D{sub 2cc} for the stomach and for the duodenum were analyzed; differences were tested for significance using the Wilcoxon signed-rank test. Results: Using a midV approach resulted in sufficient target coverage. A highly significant PTV size reduction of 13.9% (P<.001) was observed. Also, all dose parameters for the stomach and duodenum, except the D{sub 2cc} of the duodenum, improved significantly (P≤.002). Conclusions: By using the midV approach to account for respiratory-induced tumor motion, a significant PTV reduction and significant dose reductions to the stomach and to the duodenum can be achieved when irradiating pancreatic tumors.« less

  4. Fast or Slow Rescue Ventilations: A Predictive Model of Gastric Inflation.

    PubMed

    Fitz-Clarke, John R

    2018-05-01

    Rescue ventilations are given during respiratory and cardiac arrest. Tidal volume must assure oxygen delivery; however, excessive pressure applied to an unprotected airway can cause gastric inflation, regurgitation, and pulmonary aspiration. The optimal technique provides mouth pressure and breath duration that minimize gastric inflation. It remains unclear if breath delivery should be fast or slow, and how inflation time affects the division of gas flow between the lungs and esophagus. A physiological model was used to predict and compare rates of gastric inflation and to determine ideal ventilation duration. Gas flow equations were based on standard pulmonary physiology. Gastric inflation was assumed to occur whenever mouth pressure exceeded lower esophageal sphincter pressure. Mouth pressure profiles that approximated mouth-to-mouth ventilation and bag-valve-mask ventilation were investigated. Target tidal volumes were set to 0.6 and 1.0 L. Compliance and airway resistance were varied. Rapid breaths shorter than 1 s required high mouth pressures, up to 25 cm H 2 O to achieve the target lung volume, which thus promotes gastric inflation. Slow breaths longer than 1 s permitted lower mouth pressures but increased time over which airway pressure exceeded lower esophageal sphincter pressure. The gastric volume increased with breath durations that exceeded 1 s for both mouth pressure profiles. Breath duration of ∼1.0 s caused the least gastric inflation in most scenarios. Very low esophageal sphincter pressure favored a shift toward 0.5 s. High resistance and low compliance each increased gastric inflation and altered ideal breath times. The model illustrated a general theory of optimal rescue ventilation. Breath duration with an unprotected airway should be 1 s to minimize gastric inflation. Short pressure-driven and long duration-driven gastric inflation regimens provide a unifying explanation for results in past studies. Copyright © 2018 by Daedalus Enterprises.

  5. A new approach to delineating lymph node target volumes for post-operative radiotherapy in gastric cancer: A phase II trial.

    PubMed

    Haijun, Yu; Qiuji, Wu; Zhenming, Fu; Yong, Huang; Zhengkai, Liao; Conghua, Xie; Yunfeng, Zhou; Yahua, Zhong

    2015-08-01

    In the context of gastric cancer, lymph node target volume delineation for post-operative radiotherapy is currently built on the traditional system of dividing the stomach and 2-D treatment methods. Here, we have proposed a new delineation approach with irradiation indications for lymph node stations. Its safety and efficacy were evaluated in a phase II clinical trial. Fifty-four gastric cancer patients with D2 lymph node dissection received 2 cycles of FOLFOX4. They subsequently received concurrent chemoradiotherapy (45 Gy at 1.8 Gy per fraction, 5 fractions per week for 5 weeks) with a 5-fluorouracil/leucovorin regimen, followed by 4 additional FOLFOX4 cycles. The target volume included the remnant stomach, anastomosis site, tumor bed, and regional lymph nodes selected through our new approach by taking gastric arteries as references. The most common grade 3-4 adverse event was neutropenia (14.8%). Neutropenia, anemia, and nausea were common grade 1-2 toxicities. No treatment-related deaths occurred during treatment. The 3-year overall, disease-free, and locoregional recurrence-free survival rates were 81.6%, 70.2%, and 91.1%, respectively. Eight patients developed peritoneal or distant metastases. Using our new approach and irradiation indications, delineation of the target volume of post-operative lymph node stations was feasible and well tolerated after D2 resection in patients with gastric cancer. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  6. Fast and behavior-selective exploitation of a marine fish targeted by anglers

    PubMed Central

    Alós, Josep; Palmer, Miquel; Rosselló, Rosario; Arlinghaus, Robert

    2016-01-01

    Harvesting of wild-living animals is often intensive and may selectively target heritable behavioral traits. We studied the exploitation dynamics and the vulnerability consequences of individual heterogeneity in movement-related behaviors in free-ranging pearly razorfish (Xyrichthys novacula). Using underwater-video recording, we firstly document a fast and high exploitation rate of about 60% of the adult population removed in just few days after the opening of the season. Subsequently, we tagged a sample of individuals with acoustic transmitters and studied whether behavioral traits were significant predictors of the vulnerability to angling. Tagged individuals revealed repeatable behaviors in several home range-related traits, suggesting the presence of spatial behavioral types. The individuals surviving the experimental fishery showed only localized and low-intensity movement patterns. Our study provides new insights for understanding the harvesting pressures and selective properties acting on behavioral traits of recreational fishing. Many fish stocks around the globe are today predominantly exploited by recreational fisheries. The fisheries-induced change in fish behavior described here may be therefore widespread, and has the potential to alter food-webs, profitability of the fisheries and to affect stock assessment by eroding catchability in the long-term. PMID:27922022

  7. Fast and behavior-selective exploitation of a marine fish targeted by anglers

    NASA Astrophysics Data System (ADS)

    Alós, Josep; Palmer, Miquel; Rosselló, Rosario; Arlinghaus, Robert

    2016-12-01

    Harvesting of wild-living animals is often intensive and may selectively target heritable behavioral traits. We studied the exploitation dynamics and the vulnerability consequences of individual heterogeneity in movement-related behaviors in free-ranging pearly razorfish (Xyrichthys novacula). Using underwater-video recording, we firstly document a fast and high exploitation rate of about 60% of the adult population removed in just few days after the opening of the season. Subsequently, we tagged a sample of individuals with acoustic transmitters and studied whether behavioral traits were significant predictors of the vulnerability to angling. Tagged individuals revealed repeatable behaviors in several home range-related traits, suggesting the presence of spatial behavioral types. The individuals surviving the experimental fishery showed only localized and low-intensity movement patterns. Our study provides new insights for understanding the harvesting pressures and selective properties acting on behavioral traits of recreational fishing. Many fish stocks around the globe are today predominantly exploited by recreational fisheries. The fisheries-induced change in fish behavior described here may be therefore widespread, and has the potential to alter food-webs, profitability of the fisheries and to affect stock assessment by eroding catchability in the long-term.

  8. Radiotherapy planning for glioblastoma based on a tumor growth model: improving target volume delineation.

    PubMed

    Unkelbach, Jan; Menze, Bjoern H; Konukoglu, Ender; Dittmann, Florian; Le, Matthieu; Ayache, Nicholas; Shih, Helen A

    2014-02-07

    Glioblastoma differ from many other tumors in the sense that they grow infiltratively into the brain tissue instead of forming a solid tumor mass with a defined boundary. Only the part of the tumor with high tumor cell density can be localized through imaging directly. In contrast, brain tissue infiltrated by tumor cells at low density appears normal on current imaging modalities. In current clinical practice, a uniform margin, typically two centimeters, is applied to account for microscopic spread of disease that is not directly assessable through imaging. The current treatment planning procedure can potentially be improved by accounting for the anisotropy of tumor growth, which arises from different factors: anatomical barriers such as the falx cerebri represent boundaries for migrating tumor cells. In addition, tumor cells primarily spread in white matter and infiltrate gray matter at lower rate. We investigate the use of a phenomenological tumor growth model for treatment planning. The model is based on the Fisher-Kolmogorov equation, which formalizes these growth characteristics and estimates the spatial distribution of tumor cells in normal appearing regions of the brain. The target volume for radiotherapy planning can be defined as an isoline of the simulated tumor cell density. This paper analyzes the model with respect to implications for target volume definition and identifies its most critical components. A retrospective study involving ten glioblastoma patients treated at our institution has been performed. To illustrate the main findings of the study, a detailed case study is presented for a glioblastoma located close to the falx. In this situation, the falx represents a boundary for migrating tumor cells, whereas the corpus callosum provides a route for the tumor to spread to the contralateral hemisphere. We further discuss the sensitivity of the model with respect to the input parameters. Correct segmentation of the brain appears to be the most

  9. Radiotherapy planning for glioblastoma based on a tumor growth model: improving target volume delineation

    NASA Astrophysics Data System (ADS)

    Unkelbach, Jan; Menze, Bjoern H.; Konukoglu, Ender; Dittmann, Florian; Le, Matthieu; Ayache, Nicholas; Shih, Helen A.

    2014-02-01

    Glioblastoma differ from many other tumors in the sense that they grow infiltratively into the brain tissue instead of forming a solid tumor mass with a defined boundary. Only the part of the tumor with high tumor cell density can be localized through imaging directly. In contrast, brain tissue infiltrated by tumor cells at low density appears normal on current imaging modalities. In current clinical practice, a uniform margin, typically two centimeters, is applied to account for microscopic spread of disease that is not directly assessable through imaging. The current treatment planning procedure can potentially be improved by accounting for the anisotropy of tumor growth, which arises from different factors: anatomical barriers such as the falx cerebri represent boundaries for migrating tumor cells. In addition, tumor cells primarily spread in white matter and infiltrate gray matter at lower rate. We investigate the use of a phenomenological tumor growth model for treatment planning. The model is based on the Fisher-Kolmogorov equation, which formalizes these growth characteristics and estimates the spatial distribution of tumor cells in normal appearing regions of the brain. The target volume for radiotherapy planning can be defined as an isoline of the simulated tumor cell density. This paper analyzes the model with respect to implications for target volume definition and identifies its most critical components. A retrospective study involving ten glioblastoma patients treated at our institution has been performed. To illustrate the main findings of the study, a detailed case study is presented for a glioblastoma located close to the falx. In this situation, the falx represents a boundary for migrating tumor cells, whereas the corpus callosum provides a route for the tumor to spread to the contralateral hemisphere. We further discuss the sensitivity of the model with respect to the input parameters. Correct segmentation of the brain appears to be the most

  10. Risk factors for radiation pneumonitis after stereotactic radiation therapy for lung tumours: clinical usefulness of the planning target volume to total lung volume ratio.

    PubMed

    Ueyama, Tomoko; Arimura, Takeshi; Takumi, Koji; Nakamura, Fumihiko; Higashi, Ryutaro; Ito, Soichiro; Fukukura, Yoshihiko; Umanodan, Tomokazu; Nakajo, Masanori; Koriyama, Chihaya; Yoshiura, Takashi

    2018-06-01

    To identify risk factors for symptomatic radiation pneumonitis (RP) after stereotactic radiation therapy (SRT) for lung tumours. We retrospectively evaluated 68 lung tumours in 63 patients treated with SRT between 2011 and 2015. RP was graded according to the National Cancer Institute-Common Terminology Criteria for Adverse Events version 4.0. SRT was delivered at 7.0-12.0 Gy per each fraction, once daily, to a total of 48-64 Gy (median, 50 Gy). Univariate analysis was performed to assess patient- and treatment-related factors, including age, sex, smoking index (SI), pulmonary function, tumour location, serum Krebs von den Lungen-6 value (KL-6), dose-volume metrics (V5, V10, V20, V30, V40 and VS5), homogeneity index of the planning target volume (PTV), PTV dose, mean lung dose (MLD), contralateral MLD and V2, PTV volume, lung volume and the PTV/lung volume ratio (PTV/Lung). Performance of PTV/Lung in predicting symptomatic RP was also analysed using receiver operating characteristic (ROC) analysis. The median follow-up period was 21 months. 10 of 63 patients (15.9%) developed symptomatic RP after SRT. On univariate analysis, V10, V20, PTV volume and PTV/Lung were significantly associated with occurrence of RP  ≥Grade 2. ROC curves indicated that symptomatic RP could be predicted using PTV/Lung [area under curve (AUC): 0.88, confidence interval (CI: 0.78-0.95), cut-off value: 1.09, sensitivity: 90.0% and specificity: 72.4%]. PTV/Lung is a good predictor of symptomatic RP after SRT. Advances in knowledge: The cases with high PTV/Lung should be carefully monitored with caution for the occurrence of RP after SRT.

  11. Direct visuomotor mapping for fast visually-evoked arm movements.

    PubMed

    Reynolds, Raymond F; Day, Brian L

    2012-12-01

    In contrast to conventional reaction time (RT) tasks, saccadic RT's to visual targets are very fast and unaffected by the number of possible targets. This can be explained by the sub-cortical circuitry underlying eye movements, which involves direct mapping between retinal input and motor output in the superior colliculus. Here we asked if the choice-invariance established for the eyes also applies to a special class of fast visuomotor responses of the upper limb. Using a target-pointing paradigm we observed very fast reaction times (<150 ms) which were completely unaffected as the number of possible target choices was increased from 1 to 4. When we introduced a condition of altered stimulus-response mapping, RT went up and a cost of choice was observed. These results can be explained by direct mapping between visual input and motor output, compatible with a sub-cortical pathway for visual control of the upper limb. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Preliminary evidence for obesity and elevations in fasting insulin mediating associations between cortisol awakening response and hippocampal volumes and frontal atrophy.

    PubMed

    Ursache, Alexandra; Wedin, William; Tirsi, Aziz; Convit, Antonio

    2012-08-01

    Recent studies have demonstrated alterations in the cortisol awakening response (CAR) and brain abnormalities in adults with obesity and type 2 diabetes mellitus (T2DM). While adolescents with T2DM exhibit similar brain abnormalities, less is known about whether brain impairments and hypothalamic-pituitary-adrenal (HPA) axis abnormalities are already present in adolescents with pre-diabetic conditions such as insulin resistance (IR). This study included 33 adolescents with IR and 20 without IR. Adolescents with IR had a blunted CAR, smaller hippocampal volumes, and greater frontal lobe atrophy compared to controls. Mediation analyses indicated pathways whereby a smaller CAR was associated with higher BMI which was in turn associated with fasting insulin levels, which in turn was related to smaller hippocampal volume and greater frontal lobe atrophy. While we had hypothesized that HPA dysregulation may result from brain abnormalities, our findings suggest that HPA dysregulation may also impact brain structures through associations with metabolic abnormalities. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. SU-E-T-480: Radiobiological Dose Comparison of Single Fraction SRS, Multi-Fraction SRT and Multi-Stage SRS of Large Target Volumes Using the Linear-Quadratic Formula

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ding, C; Hrycushko, B; Jiang, S

    2014-06-01

    Purpose: To compare the radiobiological effect on large tumors and surrounding normal tissues from single fraction SRS, multi-fractionated SRT, and multi-staged SRS treatment. Methods: An anthropomorphic head phantom with a centrally located large volume target (18.2 cm{sup 3}) was scanned using a 16 slice large bore CT simulator. Scans were imported to the Multiplan treatment planning system where a total prescription dose of 20Gy was used for a single, three staged and three fractionated treatment. Cyber Knife treatment plans were inversely optimized for the target volume to achieve at least 95% coverage of the prescription dose. For the multistage plan,more » the target was segmented into three subtargets having similar volume and shape. Staged plans for individual subtargets were generated based on a planning technique where the beam MUs of the original plan on the total target volume are changed by weighting the MUs based on projected beam lengths within each subtarget. Dose matrices for each plan were export in DICOM format and used to calculate equivalent dose distributions in 2Gy fractions using an alpha beta ratio of 10 for the target and 3 for normal tissue. Results: Singe fraction SRS, multi-stage plan and multi-fractionated SRT plans had an average 2Gy dose equivalent to the target of 62.89Gy, 37.91Gy and 33.68Gy, respectively. The normal tissue within 12Gy physical dose region had an average 2Gy dose equivalent of 29.55Gy, 16.08Gy and 13.93Gy, respectively. Conclusion: The single fraction SRS plan had the largest predicted biological effect for the target and the surrounding normal tissue. The multi-stage treatment provided for a more potent biologically effect on target compared to the multi-fraction SRT treatments with less biological normal tissue than single-fraction SRS treatment.« less

  14. Volume Transmission in Central Dopamine and Noradrenaline Neurons and Its Astroglial Targets.

    PubMed

    Fuxe, Kjell; Agnati, Luigi F; Marcoli, Manuela; Borroto-Escuela, Dasiel O

    2015-12-01

    Already in the 1960s the architecture and pharmacology of the brainstem dopamine (DA) and noradrenaline (NA) neurons with formation of vast numbers of DA and NA terminal plexa of the central nervous system (CNS) indicated that they may not only communicate via synaptic transmission. In the 1980s the theory of volume transmission (VT) was introduced as a major communication together with synaptic transmission in the CNS. VT is an extracellular and cerebrospinal fluid transmission of chemical signals like transmitters, modulators etc. moving along energy gradients making diffusion and flow of VT signals possible. VT interacts with synaptic transmission mainly through direct receptor-receptor interactions in synaptic and extrasynaptic heteroreceptor complexes and their signaling cascades. The DA and NA neurons are specialized for extrasynaptic VT at the soma-dendrtitic and terminal level. The catecholamines released target multiple DA and adrenergic subtypes on nerve cells, astroglia and microglia which are the major cell components of the trophic units building up the neural-glial networks of the CNS. DA and NA VT can modulate not only the strength of synaptic transmission but also the VT signaling of the astroglia and microglia of high relevance for neuron-glia interactions. The catecholamine VT targeting astroglia can modulate the fundamental functions of astroglia observed in neuroenergetics, in the Glymphatic system, in the central renin-angiotensin system and in the production of long-distance calcium waves. Also the astrocytic and microglial DA and adrenergic receptor subtypes mediating DA and NA VT can be significant drug targets in neurological and psychiatric disease.

  15. Fabrication of aerogel capsule, bromine-doped capsule, and modified gold cone in modified target for the Fast Ignition Realization Experiment (FIREX) Project

    NASA Astrophysics Data System (ADS)

    Nagai, Keiji; Yang, H.; Norimatsu, T.; Azechi, H.; Belkada, F.; Fujimoto, Y.; Fujimura, T.; Fujioka, K.; Fujioka, S.; Homma, H.; Ito, F.; Iwamoto, A.; Jitsuno, T.; Kaneyasu, Y.; Nakai, M.; Nemoto, N.; Saika, H.; Shimoyama, T.; Suzuki, Y.; Yamanaka, K.; Mima, K.

    2009-09-01

    The development of target fabrication for the Fast Ignition Realization EXperiment (FIREX) Project is described in this paper. For the first stage of the FIREX Project (FIREX-I), the previously designed target has been modified by using a bromine-doped ablator and coating the inner gold cone with a low-density material. A high-quality bromine-doped capsule without vacuoles was fabricated from bromine-doped deuterated polystyrene. The gold surface was coated with a low-density material by electrochemical plating. For the cryogenic fuel target, a brand new type of aerogel material, phloroglucinol/formaldehyde (PF), was investigated and encapsulated to meet the specifications of 500 µm diameter and 20 µm thickness, with 30 nm nanopores. Polystyrene-based low-density materials were investigated and the relationship between the crosslinker content and the nanopore structure was observed.

  16. WE-DE-201-01: BEST IN PHYSICS (THERAPY): A Fast Multi-Target Inverse Treatment Planning Strategy Optimizing Dosimetric Measures for High-Dose-Rate (HDR) Brachytherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guthier, C; University Medical Center Mannheim, Mannheim; Harvard Medical School, Boston, MA

    Purpose: Inverse treatment planning (ITP) for interstitial HDR brachytherapy of gynecologic cancers seeks to maximize coverage of the clinical target volumes (tumor and vagina) while respecting dose-volume-histogram related dosimetric measures (DMs) for organs at risk (OARs). Commercially available ITP tools do not support DM-based planning because it is computationally too expensive to solve. In this study we present a novel approach that allows fast ITP for gynecologic cancers based on DMs for the first time. Methods: This novel strategy is an optimization model based on a smooth DM-based objective function. The smooth approximation is achieved by utilizing a logistic functionmore » for the evaluation of DMs. The resulting nonconvex and constrained optimization problem is then optimized with a BFGS algorithm. The model was evaluated using the implant geometry extracted from 20 patient treatment plans under an IRB-approved retrospective study. For each plan, the final DMs were evaluated and compared to the original clinical plans. The CTVs were the contoured tumor volume and the contoured surface of the vagina. Statistical significance was evaluated with a one-sided paired Wilcoxon signed-rank test. Results: As did the clinical plans, all generated plans fulfilled the defined DMs for OARs. The proposed strategy showed a statistically significant improvement (p<0.001) in coverage of the tumor and vagina, with absolute improvements of related DMs of (6.9 +/− 7.9)% and (28.2 +/− 12.0)%, respectively. This was achieved with a statistically significant (p<0.01) decrease of the high-dose-related DM for the tumor. The runtime of the optimization was (2.3 +/− 2.0) seconds. Conclusion: We demonstrated using clinical data that our novel approach allows rapid DM-based optimization with improved coverage of CTVs with fewer hot spots. Being up to three orders of magnitude faster than the current clinical practice, the method dramatically shortens planning time.« less

  17. The impact of PET/CT scanning on the size of target volumes, radiation exposure of organs at risk, TCP and NTCP, in the radiotherapy planning of non-small cell lung cancer.

    PubMed

    Vojtíšek, Radovan; Mužík, Jan; Slampa, Pavel; Budíková, Marie; Hejsek, Jaroslav; Smolák, Petr; Ferda, Jiří; Fínek, Jindřich

    2014-05-01

    To compare radiotherapy plans made according to CT and PET/CT and to investigate the impact of changes in target volumes on tumour control probability (TCP), normal tissue complication probability (NTCP) and the impact of PET/CT on the staging and treatment strategy. Contemporary studies have proven that PET/CT attains higher sensitivity and specificity in the diagnosis of lung cancer and also leads to higher accuracy than CT alone in the process of target volume delineation in NSCLC. Between October 2009 and March 2012, 31 patients with locally advanced NSCLC, who had been referred to radical radiotherapy were involved in our study. They all underwent planning PET/CT examination. Then we carried out two separate delineations of target volumes and two radiotherapy plans and we compared the following parameters of those plans: staging, treatment purpose, the size of GTV and PTV and the exposure of organs at risk (OAR). TCP and NTCP were also compared. PET/CT information led to a significant decrease in the sizes of target volumes, which had the impact on the radiation exposure of OARs. The reduction of target volume sizes was not reflected in the significant increase of the TCP value. We found that there is a very strong direct linear relationship between all evaluated dosimetric parameters and NTCP values of all evaluated OARs. Our study found that the use of planning PET/CT in the radiotherapy planning of NSCLC has a crucial impact on the precise determination of target volumes, more precise staging of the disease and thus also on possible changes of treatment strategy.

  18. Influence of FDG-PET on primary nodal target volume definition for head and neck carcinomas.

    PubMed

    van Egmond, Sylvia L; Piscaer, Vera; Janssen, Luuk M; Stegeman, Inge; Hobbelink, Monique G; Grolman, Wilko; Terhaard, Chris H

    The role of 2-[ 18 F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in routine diagnostic staging remains controversial. In case of discordance between FDG-PET and CT, a compromise has to be made between the risk of false positive FDG-PET and the risk of delaying appropriate salvage intervention. Second, with intensity modulated radiation therapy (IMRT), smaller radiation fields allow tissue sparing, but could also lead to more marginal failures. We retrospectively studied 283 patients with head and neck carcinoma scheduled for radiotherapy between 2002 and 2010. We analyzed the influence of FDG-PET/CT versus CT alone on defining nodal target volume definition and evaluated its long-term clinical results. Second, the location of nodal recurrences was related to the radiation regional dose distribution. In 92 patients, CT and FDG-PET, performed in mold, showed discordant results. In 33%, nodal staging was altered by FDG-PET. In 24%, FDG-PET also led to an alteration in nodal treatment, including a nodal upstage of 18% and downstage of 6%. In eight of these 92 patients, a regional recurrence occurred. Only two patients had a recurrence in the discordant node on FDG-PET and CT and both received a boost (high dose radiation). These results support the complementary value of FDG-PET/CT compared to CT alone in defining nodal target volume definition for radiotherapy of head and neck cancer.

  19. Positive FAST without hemoperitoneum due to fluid resuscitation in blunt trauma.

    PubMed

    Slutzman, Jonathan E; Arvold, Lisa A; Rempell, Joshua S; Stone, Michael B; Kimberly, Heidi H

    2014-10-01

    The focused assessment with sonography in trauma (FAST) examination is an important screening tool in the evaluation of blunt trauma patients. To describe a case of a hemodynamically unstable polytrauma patient with positive FAST due to fluid resuscitation after blunt trauma. We describe a case of a hemodynamically unstable polytrauma patient who underwent massive volume resuscitation prior to transfer from a community hospital to a trauma center. On arrival at the receiving institution, the FAST examination was positive for free intraperitoneal fluid, but no hemoperitoneum or significant intra-abdominal injuries were found during laparotomy. In this case, it is postulated that transudative intraperitoneal fluid secondary to massive volume resuscitation resulted in a positive FAST examination. This case highlights potential issues specific to resuscitated trauma patients with prolonged transport times. Further study is likely needed to assess what changes, if any, should be made in algorithms to address the effect of prior resuscitative efforts on the test characteristics of the FAST examination. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Fast Pb-glass neutron-to-light converter for ICF (Inertial Confinement Fusion) target burn history measurements

    NASA Astrophysics Data System (ADS)

    Lerche, R. A.; Cable, M. D.; Phillion, D. W.

    1990-09-01

    We are developing a streak camera based instrument to diagnose the fusion reaction rate (burn history) within laser-driven ICF targets filled with D-T fuel. Recently, we attempted measurements using the 16.7 MeV gamma ray emitted in the T(d,gamma)He(5) fusion reaction. Pb glass which has a large cross section for pair production acts as a gamma-ray-to-light converter. Gamma rays interact within the glass to form electron-positron pairs that produce large amounts (1000 photons/gamma ray) of prompt (less than 10 ps) Cerenkov light as they slow down. In our experimental instrument, an f/10 Cassegrain telescope optically couples light produced within the converter to a streak camera having 20-ps resolution. Experiments using high-yield (10(exp 13) D-T neutrons), direct-drive targets at Nova produced good signals with widths of 200 ps. Time-of-flight measurements show the signals to be induced by neutrons rather than gamma rays. The Pb glass appears to act as a fast neutron-to-light converter. We continue to study the interactions process and the possibility of using the 16.7 MeV gamma rays for burn time measurements.

  1. Aqueous stream characterization from biomass fast pyrolysis and catalytic fast pyrolysis

    DOE PAGES

    Black, Brenna A.; Michener, William E.; Ramirez, Kelsey J.; ...

    2016-09-05

    Here, biomass pyrolysis offers a promising means to rapidly depolymerize lignocellulosic biomass for subsequent catalytic upgrading to renewable fuels. Substantial efforts are currently ongoing to optimize pyrolysis processes including various fast pyrolysis and catalytic fast pyrolysis schemes. In all cases, complex aqueous streams are generated containing solubilized organic compounds that are not converted to target fuels or chemicals and are often slated for wastewater treatment, in turn creating an economic burden on the biorefinery. Valorization of the species in these aqueous streams, however, offers significant potential for substantially improving the economics and sustainability of thermochemical biorefineries. To that end, heremore » we provide a thorough characterization of the aqueous streams from four pilot-scale pyrolysis processes: namely, from fast pyrolysis, fast pyrolysis with downstream fractionation, in situ catalytic fast pyrolysis, and ex situ catalytic fast pyrolysis. These configurations and processes represent characteristic pyrolysis processes undergoing intense development currently. Using a comprehensive suite of aqueous-compatible analytical techniques, we quantitatively characterize between 12 g kg -1 of organic carbon of a highly aqueous catalytic fast pyrolysis stream and up to 315 g kg -1 of organic carbon present in the fast pyrolysis aqueous streams. In all cases, the analysis ranges between 75 and 100% of mass closure. The composition and stream properties closely match the nature of pyrolysis processes, with high contents of carbohydrate-derived compounds in the fast pyrolysis aqueous phase, high acid content in nearly all streams, and mostly recalcitrant phenolics in the heavily deoxygenated ex situ catalytic fast pyrolysis stream. Overall, this work provides a detailed compositional analysis of aqueous streams from leading thermochemical processes -- analyses that are critical for subsequent development of selective

  2. Aqueous stream characterization from biomass fast pyrolysis and catalytic fast pyrolysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Black, Brenna A.; Michener, William E.; Ramirez, Kelsey J.

    Here, biomass pyrolysis offers a promising means to rapidly depolymerize lignocellulosic biomass for subsequent catalytic upgrading to renewable fuels. Substantial efforts are currently ongoing to optimize pyrolysis processes including various fast pyrolysis and catalytic fast pyrolysis schemes. In all cases, complex aqueous streams are generated containing solubilized organic compounds that are not converted to target fuels or chemicals and are often slated for wastewater treatment, in turn creating an economic burden on the biorefinery. Valorization of the species in these aqueous streams, however, offers significant potential for substantially improving the economics and sustainability of thermochemical biorefineries. To that end, heremore » we provide a thorough characterization of the aqueous streams from four pilot-scale pyrolysis processes: namely, from fast pyrolysis, fast pyrolysis with downstream fractionation, in situ catalytic fast pyrolysis, and ex situ catalytic fast pyrolysis. These configurations and processes represent characteristic pyrolysis processes undergoing intense development currently. Using a comprehensive suite of aqueous-compatible analytical techniques, we quantitatively characterize between 12 g kg -1 of organic carbon of a highly aqueous catalytic fast pyrolysis stream and up to 315 g kg -1 of organic carbon present in the fast pyrolysis aqueous streams. In all cases, the analysis ranges between 75 and 100% of mass closure. The composition and stream properties closely match the nature of pyrolysis processes, with high contents of carbohydrate-derived compounds in the fast pyrolysis aqueous phase, high acid content in nearly all streams, and mostly recalcitrant phenolics in the heavily deoxygenated ex situ catalytic fast pyrolysis stream. Overall, this work provides a detailed compositional analysis of aqueous streams from leading thermochemical processes -- analyses that are critical for subsequent development of selective

  3. A Compact Multiphoton 3D Imaging System for Recording Fast Neuronal Activity

    PubMed Central

    Vučinić, Dejan; Sejnowski, Terrence J.

    2007-01-01

    We constructed a simple and compact imaging system designed specifically for the recording of fast neuronal activity in a 3D volume. The system uses an Yb:KYW femtosecond laser we designed for use with acousto-optic deflection. An integrated two-axis acousto-optic deflector, driven by digitally synthesized signals, can target locations in three dimensions. Data acquisition and the control of scanning are performed by a LeCroy digital oscilloscope. The total cost of construction was one order of magnitude lower than that of a typical Ti:sapphire system. The entire imaging apparatus, including the laser, fits comfortably onto a small rig for electrophysiology. Despite the low cost and simplicity, the convergence of several new technologies allowed us to achieve the following capabilities: i) full-frame acquisition at video rates suitable for patch clamping; ii) random access in under ten microseconds with dwelling ability in the nominal focal plane; iii) three-dimensional random access with the ability to perform fast volume sweeps at kilohertz rates; and iv) fluorescence lifetime imaging. We demonstrate the ability to record action potentials with high temporal resolution using intracellularly loaded potentiometric dye di-2-ANEPEQ. Our design proffers easy integration with electrophysiology and promises a more widespread adoption of functional two-photon imaging as a tool for the study of neuronal activity. The software and firmware we developed is available for download at http://neurospy.org/ under an open source license. PMID:17684546

  4. Is the Ellipsoid Formula the New Standard for 3-Tesla MRI Prostate Volume Calculation without Endorectal Coil?

    PubMed

    Haas, Matthias; Günzel, Karsten; Miller, Kurt; Hamm, Bernd; Cash, Hannes; Asbach, Patrick

    2017-01-01

    Prostate volume in multiparametric MRI (mpMRI) is of clinical importance. For 3-Tesla mpMRI without endorectal coil, there is no distinctive standard for volume calculation. We tested the accuracy of the ellipsoid formula with planimetric volume measurements as reference and investigated the correlation of gland volume and cancer detection rate on MRI/ultrasound (MRI/US) fusion-guided biopsy. One hundred forty-three patients with findings on 3-Tesla mpMRI suspicious of cancer and subsequent MRI/US fusion-guided targeted biopsy and additional systematic biopsy were analyzed. T2-weighted images were used for measuring the prostate diameters and for planimetric volume measurement by a segmentation software. Planimetric and calculated prostate volumes were compared with clinical data. The median prostate volume was 48.1 ml (interquartile range (IQR) 36.9-62.1 ml). Volume calculated by the ellipsoid formula showed a strong concordance with planimetric volume, with a tendency to underestimate prostate volume (median volume 43.1 ml (IQR 31.2-58.8 ml); r = 0.903, p < 0.001). There was a moderate, significant inverse correlation of prostate volume to a positive biopsy result (r = -0.24, p = 0.004). The ellipsoid formula gives sufficient approximation of prostate volume on 3-Tesla mpMRI without endorectal coil. It allows a fast, valid volume calculation in prostate MRI datasets. © 2016 S. Karger AG, Basel.

  5. Phonological and Orthographic Overlap Effects in Fast and Masked Priming

    PubMed Central

    Frisson, Steven; Bélanger, Nathalie N.; Rayner, Keith

    2014-01-01

    We investigated how orthographic and phonological information is activated during reading, using a fast priming task, and during single word recognition, using masked priming. Specifically, different types of overlap between prime and target were contrasted: high orthographic and high phonological overlap (track-crack), high orthographic and low phonological overlap (bear-gear), or low orthographic and high phonological overlap (fruit-chute). In addition, we examined whether (orthographic) beginning overlap (swoop-swoon) yielded the same priming pattern as end (rhyme) overlap (track-crack). Prime durations were 32 and 50ms in the fast priming version, and 50ms in the masked priming version, and mode of presentation (prime and target in lower case) was identical. The fast priming experiment showed facilitatory priming effects when both orthography and phonology overlapped, with no apparent differences between beginning and end overlap pairs. Facilitation was also found when prime and target only overlapped orthographically. In contrast, the masked priming experiment showed inhibition for both types of end overlap pairs (with and without phonological overlap), and no difference for begin overlap items. When prime and target only shared principally phonological information, facilitation was only found with a long prime duration in the fast priming experiment, while no differences were found in the masked priming version. These contrasting results suggest that fast priming and masked priming do not necessarily tap into the same type of processing. PMID:24365065

  6. Comparative Study With New Accuracy Metrics for Target Volume Contouring in PET Image Guided Radiation Therapy

    PubMed Central

    Shepherd, T; Teras, M; Beichel, RR; Boellaard, R; Bruynooghe, M; Dicken, V; Gooding, MJ; Julyan, PJ; Lee, JA; Lefèvre, S; Mix, M; Naranjo, V; Wu, X; Zaidi, H; Zeng, Z; Minn, H

    2017-01-01

    The impact of positron emission tomography (PET) on radiation therapy is held back by poor methods of defining functional volumes of interest. Many new software tools are being proposed for contouring target volumes but the different approaches are not adequately compared and their accuracy is poorly evaluated due to the ill-definition of ground truth. This paper compares the largest cohort to date of established, emerging and proposed PET contouring methods, in terms of accuracy and variability. We emphasize spatial accuracy and present a new metric that addresses the lack of unique ground truth. Thirty methods are used at 13 different institutions to contour functional volumes of interest in clinical PET/CT and a custom-built PET phantom representing typical problems in image guided radiotherapy. Contouring methods are grouped according to algorithmic type, level of interactivity and how they exploit structural information in hybrid images. Experiments reveal benefits of high levels of user interaction, as well as simultaneous visualization of CT images and PET gradients to guide interactive procedures. Method-wise evaluation identifies the danger of over-automation and the value of prior knowledge built into an algorithm. PMID:22692898

  7. 3D prostate MR-TRUS non-rigid registration using dual optimization with volume-preserving constraint

    NASA Astrophysics Data System (ADS)

    Qiu, Wu; Yuan, Jing; Fenster, Aaron

    2016-03-01

    We introduce an efficient and novel convex optimization-based approach to the challenging non-rigid registration of 3D prostate magnetic resonance (MR) and transrectal ultrasound (TRUS) images, which incorporates a new volume preserving constraint to essentially improve the accuracy of targeting suspicious regions during the 3D TRUS guided prostate biopsy. Especially, we propose a fast sequential convex optimization scheme to efficiently minimize the employed highly nonlinear image fidelity function using the robust multi-channel modality independent neighborhood descriptor (MIND) across the two modalities of MR and TRUS. The registration accuracy was evaluated using 10 patient images by calculating the target registration error (TRE) using manually identified corresponding intrinsic fiducials in the whole prostate gland. We also compared the MR and TRUS manually segmented prostate surfaces in the registered images in terms of the Dice similarity coefficient (DSC), mean absolute surface distance (MAD), and maximum absolute surface distance (MAXD). Experimental results showed that the proposed method with the introduced volume-preserving prior significantly improves the registration accuracy comparing to the method without the volume-preserving constraint, by yielding an overall mean TRE of 2:0+/-0:7 mm, and an average DSC of 86:5+/-3:5%, MAD of 1:4+/-0:6 mm and MAXD of 6:5+/-3:5 mm.

  8. Changes in the planning target volume and liver volume dose based on the selected respiratory phase in respiratory-gated radiation therapy for a hepatocellular carcinoma

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Seung; Im, In-Chul; Kang, Su-Man; Goo, Eun-Hoe; Baek, Seong-Min

    2013-11-01

    The aim of this study was to quantitatively analyze the changes in the planning target volume (PTV) and liver volume dose based on the respiratory phase to identify the optimal respiratory phase for respiratory-gated radiation therapy for a hepatocellular carcinoma (HCC). Based on the standardized procedure for respiratory-gated radiation therapy, we performed a 4-dimensional computed tomography simulation for 0 ˜ 90%, 30 ˜ 70%, and 40 ˜ 60% respiratory phases to assess the respiratory stability (S R ) and the defined PTV i for each respiratory phase i. A treatment plan was established, and the changes in the PTV i and dose volume of the liver were quantitatively analyzed. Most patients (91.5%) passed the respiratory stability test (S R = 0.111 ± 0.015). With standardized respiration training exercises, we were able to minimize the overall systematic error caused by irregular respiration. Furthermore, a quantitative analysis to identify the optimal respiratory phase revealed that when a short respiratory phase (40 ˜ 60%) was used, the changes in the PTV were concentrated inside the center line; thus, we were able to obtain both a PTV margin accounting for respiration and a uniform radiation dose within the PTV.

  9. The effect of pre-anaesthetic fasting time and type of food on gastric content volume and acidity in dogs.

    PubMed

    Savvas, Ioannis; Rallis, Timoleon; Raptopoulos, Dimitris

    2009-11-01

    To investigate the effect of pre-anaesthetic fasting time and variety of food on gastric content (GC) volume and pH in dogs. Randomized, cross-over, prospective experimental study. Fifteen mongrel dogs (nine females and six males 1-4 years old, weighing 10-24.5 kg). Each dog received the same seven treatments in random order: dry food 3 hours before anaesthesia (BA) (treatment 3D), canned food (half daily rate) 3 hours BA (treatment 3C), 0% fat cow milk 3 hours BA (treatment 3M), dry food 10 hours BA (treatment 10D), canned food 10 hours BA (treatment 10C), low fat canned food 10 hours BA (treatment 10F) and low protein canned food 10 hours BA (treatment 10P). All animals were pre-medicated with propionyl promazine and anaesthesia was induced with thiopental sodium and maintained with halothane. GC was aspirated using an orogastric catheter and its volume and pH were measured. Treatment 10F had significantly lower GC pH than all the 3-hour treatments. Treatments 10D and 10P had significantly lower pH than treatments 3D and 3C. Treatment 3M had significantly lower pH than the other 3-hour treatments. Treatment 3D had significantly greater gastric volume than treatments 3M, 10C, 10F and 10P. Canned food at half the daily rate administered 3 hours before anaesthesia did not increase significantly the GC volume compared to the other types of food used. The GC pH was also high. This type of food fed 3 hours before induction of anaesthesia may be of benefit in reduction of the incidence of gastro-oesophageal reflux during anaesthesia in dogs.

  10. Towards fast online intrafraction replanning for free-breathing stereotactic body radiation therapy with the MR-linac.

    PubMed

    Kontaxis, C; Bol, G H; Stemkens, B; Glitzner, M; Prins, F M; Kerkmeijer, L G W; Lagendijk, J J W; Raaymakers, B W

    2017-08-21

    The hybrid MRI-radiotherapy machines, like the MR-linac (Elekta AB, Stockholm, Sweden) installed at the UMC Utrecht (Utrecht, The Netherlands), will be able to provide real-time patient imaging during treatment. In order to take advantage of the system's capabilities and enable online adaptive treatments, a new generation of software should be developed, ranging from motion estimation to treatment plan adaptation. In this work we present a proof of principle adaptive pipeline designed for high precision stereotactic body radiation therapy (SBRT) suitable for sites affected by respiratory motion, like renal cell carcinoma (RCC). We utilized our research MRL treatment planning system (MRLTP) to simulate a single fraction 25 Gy free-breathing SBRT treatment for RCC by performing inter-beam replanning for two patients and one volunteer. The simulated pipeline included a combination of (pre-beam) 4D-MRI and (online) 2D cine-MR acquisitions. The 4DMRI was used to generate the mid-position reference volume, while the cine-MRI, via an in-house motion model, provided three-dimensional (3D) deformable vector fields (DVFs) describing the anatomical changes during treatment. During the treatment fraction, at an inter-beam interval, the mid-position volume of the patient was updated and the delivered dose was accurately reconstructed on the underlying motion calculated by the model. Fast online replanning, targeting the latest anatomy and incorporating the previously delivered dose was then simulated with MRLTP. The adaptive treatment was compared to a conventional mid-position SBRT plan with a 3 mm planning target volume margin reconstructed on the same motion trace. We demonstrate that our system produced tighter dose distributions and thus spared the healthy tissue, while delivering more dose to the target. The pipeline was able to account for baseline variations/drifts that occurred during treatment ensuring target coverage at the end of the treatment fraction.

  11. Towards fast online intrafraction replanning for free-breathing stereotactic body radiation therapy with the MR-linac

    NASA Astrophysics Data System (ADS)

    Kontaxis, C.; Bol, G. H.; Stemkens, B.; Glitzner, M.; Prins, F. M.; Kerkmeijer, L. G. W.; Lagendijk, J. J. W.; Raaymakers, B. W.

    2017-09-01

    The hybrid MRI-radiotherapy machines, like the MR-linac (Elekta AB, Stockholm, Sweden) installed at the UMC Utrecht (Utrecht, The Netherlands), will be able to provide real-time patient imaging during treatment. In order to take advantage of the system’s capabilities and enable online adaptive treatments, a new generation of software should be developed, ranging from motion estimation to treatment plan adaptation. In this work we present a proof of principle adaptive pipeline designed for high precision stereotactic body radiation therapy (SBRT) suitable for sites affected by respiratory motion, like renal cell carcinoma (RCC). We utilized our research MRL treatment planning system (MRLTP) to simulate a single fraction 25 Gy free-breathing SBRT treatment for RCC by performing inter-beam replanning for two patients and one volunteer. The simulated pipeline included a combination of (pre-beam) 4D-MRI and (online) 2D cine-MR acquisitions. The 4DMRI was used to generate the mid-position reference volume, while the cine-MRI, via an in-house motion model, provided three-dimensional (3D) deformable vector fields (DVFs) describing the anatomical changes during treatment. During the treatment fraction, at an inter-beam interval, the mid-position volume of the patient was updated and the delivered dose was accurately reconstructed on the underlying motion calculated by the model. Fast online replanning, targeting the latest anatomy and incorporating the previously delivered dose was then simulated with MRLTP. The adaptive treatment was compared to a conventional mid-position SBRT plan with a 3 mm planning target volume margin reconstructed on the same motion trace. We demonstrate that our system produced tighter dose distributions and thus spared the healthy tissue, while delivering more dose to the target. The pipeline was able to account for baseline variations/drifts that occurred during treatment ensuring target coverage at the end of the treatment fraction.

  12. FAST - FREEDOM ASSEMBLY SEQUENCING TOOL PROTOTYPE

    NASA Technical Reports Server (NTRS)

    Borden, C. S.

    1994-01-01

    FAST is a project management tool designed to optimize the assembly sequence of Space Station Freedom. An appropriate assembly sequence coordinates engineering, design, utilization, transportation availability, and operations requirements. Since complex designs tend to change frequently, FAST assesses the system level effects of detailed changes and produces output metrics that identify preferred assembly sequences. FAST incorporates Space Shuttle integration, Space Station hardware, on-orbit operations, and programmatic drivers as either precedence relations or numerical data. Hardware sequencing information can either be input directly and evaluated via the "specified" mode of operation or evaluated from the input precedence relations in the "flexible" mode. In the specified mode, FAST takes as its input a list of the cargo elements assigned to each flight. The program determines positions for the cargo elements that maximize the center of gravity (c.g.) margin. These positions are restricted by the geometry of the cargo elements and the location of attachment fittings both in the orbiter and on the cargo elements. FAST calculates every permutation of cargo element location according to its height, trunnion fitting locations, and required intercargo element spacing. Each cargo element is tested in both its normal and reversed orientation (rotated 180 degrees). The best solution is that which maximizes the c.g. margin for each flight. In the flexible mode, FAST begins with the first flight and determines all feasible combinations of cargo elements according to mass, volume, EVA, and precedence relation constraints. The program generates an assembly sequence that meets mass, volume, position, EVA, and precedence constraints while minimizing the total number of Shuttle flights required. Issues associated with ground operations, spacecraft performance, logistics requirements and user requirements will be addressed in future versions of the model. FAST is written in C

  13. Bar coded retroreflective target

    DOEpatents

    Vann, Charles S.

    2000-01-01

    This small, inexpensive, non-contact laser sensor can detect the location of a retroreflective target in a relatively large volume and up to six degrees of position. The tracker's laser beam is formed into a plane of light which is swept across the space of interest. When the beam illuminates the retroreflector, some of the light returns to the tracker. The intensity, angle, and time of the return beam is measured to calculate the three dimensional location of the target. With three retroreflectors on the target, the locations of three points on the target are measured, enabling the calculation of all six degrees of target position. Until now, devices for three-dimensional tracking of objects in a large volume have been heavy, large, and very expensive. Because of the simplicity and unique characteristics of this tracker, it is capable of three-dimensional tracking of one to several objects in a large volume, yet it is compact, light-weight, and relatively inexpensive. Alternatively, a tracker produces a diverging laser beam which is directed towards a fixed position, and senses when a retroreflective target enters the fixed field of view. An optically bar coded target can be read by the tracker to provide information about the target. The target can be formed of a ball lens with a bar code on one end. As the target moves through the field, the ball lens causes the laser beam to scan across the bar code.

  14. A clip-based protocol for breast boost radiotherapy provides clear target visualisation and demonstrates significant volume reduction over time

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lewis, Lorraine; Cox, Jennifer; Faculty of Health Sciences, University of Sydney, Sydney, New South Wales

    2015-09-15

    The clinical target volume (CTV) for early stage breast cancer is difficult to clearly identify on planning computed tomography (CT) scans. Surgical clips inserted around the tumour bed should help to identify the CTV, particularly if the seroma has been reabsorbed, and enable tracking of CTV changes over time. A surgical clip-based CTV delineation protocol was introduced. CTV visibility and its post-operative shrinkage pattern were assessed. The subjects were 27 early stage breast cancer patients receiving post-operative radiotherapy alone and 15 receiving post-operative chemotherapy followed by radiotherapy. The radiotherapy alone (RT/alone) group received a CT scan at median 25 daysmore » post-operatively (CT1rt) and another at 40 Gy, median 68 days (CT2rt). The chemotherapy/RT group (chemo/RT) received a CT scan at median 18 days post-operatively (CT1ch), a planning CT scan at median 126 days (CT2ch), and another at 40 Gy (CT3ch). There was no significant difference (P = 0.08) between the initial mean CTV for each cohort. The RT/alone cohort showed significant CTV volume reduction of 38.4% (P = 0.01) at 40 Gy. The Chemo/RT cohort had significantly reduced volumes between CT1ch: median 54 cm{sup 3} (4–118) and CT2ch: median 16 cm{sup 3}, (2–99), (P = 0.01), but no significant volume reduction thereafter. Surgical clips enable localisation of the post-surgical seroma for radiotherapy targeting. Most seroma shrinkage occurs early, enabling CT treatment planning to take place at 7 weeks, which is within the 9 weeks recommended to limit disease recurrence.« less

  15. Laser Hole Boring into Overdense Plasma and Relativistic Electron Currents for Fast Ignition of ICF Targets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pukhov, A.; Meyer-ter-Vehn, J.

    Laser hole boring and relativistic electron transport into plasma of 10 times critical density is studied by means of 2D particle-in-cell simulation. At intensities of I{sub 0}{lambda}{sup 2}=10{sup 20} W(cm){sup {minus}2} {mu}m{sup 2}, a channel 12{lambda} deep and 3{lambda} in diameter has formed after 200 laser cycles. The laser driven electron current carries up to 40{percent} of the incident laser power. When penetrating the overdense region, it breaks up into several filaments at early times, but is channeled into a single magnetized jet later on. These features are essential for fast ignition of targets for inertial confinement fusion (ICF). {copyright}more » {ital 1997} {ital The American Physical Society}« less

  16. Fast targeted analysis of 132 acidic and neutral drugs and poisons in whole blood using LC-MS/MS.

    PubMed

    Di Rago, Matthew; Saar, Eva; Rodda, Luke N; Turfus, Sophie; Kotsos, Alex; Gerostamoulos, Dimitri; Drummer, Olaf H

    2014-10-01

    The aim of this study was to develop an LC-MS/MS based screening technique that covers a broad range of acidic and neutral drugs and poisons by combining a small sample volume and efficient extraction technique with simple automated data processing. After protein precipitation of 100μL of whole blood, 132 common acidic and neutral drugs and poisons including non-steroidal anti-inflammatory drugs, barbiturates, anticonvulsants, antidiabetics, muscle relaxants, diuretics and superwarfarin rodenticides (47 quantitated, 85 reported as detected) were separated using a Shimadzu Prominence HPLC system with a C18 separation column (Kinetex XB-C18, 4.6mm×150mm, 5μm), using gradient elution with a mobile phase of 25mM ammonium acetate buffer (pH 7.5)/acetonitrile. The drugs were detected using an ABSciex(®) API 2000 LC-MS/MS system (ESI+ and -, MRM mode, two transitions per analyte). The method was fully validated in accordance with international guidelines. Quantification data obtained using one-point calibration compared favorably to that using multiple calibrants. The presented LC-MS/MS assay has proven to be applicable for determination of the analytes in blood. The fast and reliable extraction method combined with automated processing gives the opportunity for high throughput and fast turnaround times for forensic and clinical toxicology. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  17. Single-photon sensitive fast ebCMOS camera system for multiple-target tracking of single fluorophores: application to nano-biophotonics

    NASA Astrophysics Data System (ADS)

    Cajgfinger, Thomas; Chabanat, Eric; Dominjon, Agnes; Doan, Quang T.; Guerin, Cyrille; Houles, Julien; Barbier, Remi

    2011-03-01

    Nano-biophotonics applications will benefit from new fluorescent microscopy methods based essentially on super-resolution techniques (beyond the diffraction limit) on large biological structures (membranes) with fast frame rate (1000 Hz). This trend tends to push the photon detectors to the single-photon counting regime and the camera acquisition system to real time dynamic multiple-target tracing. The LUSIPHER prototype presented in this paper aims to give a different approach than those of Electron Multiplied CCD (EMCCD) technology and try to answer to the stringent demands of the new nano-biophotonics imaging techniques. The electron bombarded CMOS (ebCMOS) device has the potential to respond to this challenge, thanks to the linear gain of the accelerating high voltage of the photo-cathode, to the possible ultra fast frame rate of CMOS sensors and to the single-photon sensitivity. We produced a camera system based on a 640 kPixels ebCMOS with its acquisition system. The proof of concept for single-photon based tracking for multiple single-emitters is the main result of this paper.

  18. A technique for fast and accurate measurement of hand volumes using Archimedes' principle.

    PubMed

    Hughes, S; Lau, J

    2008-03-01

    A new technique for measuring hand volumes using Archimedes principle is described. The technique involves the immersion of a hand in a water container placed on an electronic balance. The volume is given by the change in weight divided by the density of water. This technique was compared with the more conventional technique of immersing an object in a container with an overflow spout and collecting and weighing the volume of overflow water. The hand volume of two subjects was measured. Hand volumes were 494 +/- 6 ml and 312 +/- 7 ml for the immersion method and 476 +/- 14 ml and 302 +/- 8 ml for the overflow method for the two subjects respectively. Using plastic test objects, the mean difference between the actual and measured volume was -0.3% and 2.0% for the immersion and overflow techniques respectively. This study shows that hand volumes can be obtained more quickly than the overflow method. The technique could find an application in clinics where frequent hand volumes are required.

  19. Comparison of five segmentation tools for 18F-fluoro-deoxy-glucose-positron emission tomography-based target volume definition in head and neck cancer.

    PubMed

    Schinagl, Dominic A X; Vogel, Wouter V; Hoffmann, Aswin L; van Dalen, Jorn A; Oyen, Wim J; Kaanders, Johannes H A M

    2007-11-15

    Target-volume delineation for radiation treatment to the head and neck area traditionally is based on physical examination, computed tomography (CT), and magnetic resonance imaging. Additional molecular imaging with (18)F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) may improve definition of the gross tumor volume (GTV). In this study, five methods for tumor delineation on FDG-PET are compared with CT-based delineation. Seventy-eight patients with Stages II-IV squamous cell carcinoma of the head and neck area underwent coregistered CT and FDG-PET. The primary tumor was delineated on CT, and five PET-based GTVs were obtained: visual interpretation, applying an isocontour of a standardized uptake value of 2.5, using a fixed threshold of 40% and 50% of the maximum signal intensity, and applying an adaptive threshold based on the signal-to-background ratio. Absolute GTV volumes were compared, and overlap analyses were performed. The GTV method of applying an isocontour of a standardized uptake value of 2.5 failed to provide successful delineation in 45% of cases. For the other PET delineation methods, volume and shape of the GTV were influenced heavily by the choice of segmentation tool. On average, all threshold-based PET-GTVs were smaller than on CT. Nevertheless, PET frequently detected significant tumor extension outside the GTV delineated on CT (15-34% of PET volume). The choice of segmentation tool for target-volume definition of head and neck cancer based on FDG-PET images is not trivial because it influences both volume and shape of the resulting GTV. With adequate delineation, PET may add significantly to CT- and physical examination-based GTV definition.

  20. Density overwrites of internal tumor volumes in intensity modulated proton therapy plans for mobile lung tumors

    NASA Astrophysics Data System (ADS)

    Botas, Pablo; Grassberger, Clemens; Sharp, Gregory; Paganetti, Harald

    2018-02-01

    The purpose of this study was to investigate internal tumor volume density overwrite strategies to minimize intensity modulated proton therapy (IMPT) plan degradation of mobile lung tumors. Four planning paradigms were compared for nine lung cancer patients. Internal gross tumor volume (IGTV) and internal clinical target volume (ICTV) structures were defined encompassing their respective volumes in every 4DCT phase. The paradigms use different planning CT (pCT) created from the average intensity projection (AIP) of the 4DCT, overwriting the density within the IGTV to account for movement. The density overwrites were: (a) constant filling with 100 HU (C100) or (b) 50 HU (C50), (c) maximum intensity projection (MIP) across phases, and (d) water equivalent path length (WEPL) consideration from beam’s-eye-view. Plans were created optimizing dose-influence matrices calculated with fast GPU Monte Carlo (MC) simulations in each pCT. Plans were evaluated with MC on the 4DCTs using a model of the beam delivery time structure. Dose accumulation was performed using deformable image registration. Interplay effect was addressed applying 10 times rescanning. Significantly less DVH metrics degradation occurred when using MIP and WEPL approaches. Target coverage (D99≥slant 70 Gy(RBE)) was fulfilled in most cases with MIP and WEPL (D{{99}WEPL}=69.2+/- 4.0 Gy (RBE)), keeping dose heterogeneity low (D5-D{{95}WEPL}=3.9+/- 2.0 Gy(RBE)). The mean lung dose was kept lowest by the WEPL strategy, as well as the maximum dose to organs at risk (OARs). The impact on dose levels in the heart, spinal cord and esophagus were patient specific. Overall, the WEPL strategy gives the best performance and should be preferred when using a 3D static geometry for lung cancer IMPT treatment planning. Newly available fast MC methods make it possible to handle long simulations based on 4D data sets to perform studies with high accuracy and efficiency, even prior to individual treatment planning.

  1. Impact of case volume on outcome and performance of targeted temperature management in out-of-hospital cardiac arrest survivors.

    PubMed

    Lee, Seung Joon; Jeung, Kyung Woon; Lee, Byung Kook; Min, Yong Il; Park, Kyu Nam; Suh, Gil Joon; Kim, Kyung Su; Kang, Gu Hyun

    2015-01-01

    This study aimed to determine the effect of case volume on targeted temperature management (TTM) performance, incidence of adverse events, and neurologic outcome in comatose out-of-hospital cardiac arrest (OHCA) survivors treated with TTM. We used a Web-based, multicenter registry (Korean Hypothermia Network registry), to which 24 hospitals throughout the Republic of Korea participated to study adult (≥18 years) comatose out-of-hospital cardiac arrest patients treated with TTM between 2007 and 2012. The primary outcome was neurologic outcome at hospital discharge. The secondary outcomes were inhospital mortality, TTM performance, and adverse events. We extracted propensity-matched cohorts to control for bias. Multivariate logistic regression analysis was performed to assess independent risk factors for neurologic outcome. A total of 901 patients were included in this study; 544 (60.4%) survived to hospital discharge, and 248 (27.5%) were discharged with good neurologic outcome. The high-volume hospitals initiated TTM significantly earlier and had lower rates of hyperglycemia, bleeding, hypotension, and rebound hyperthermia. However, neurologic outcome and inhospital mortality were comparable between high-volume (27.7% and 44.6%, respectively) and low-volume hospitals (21.1% and 40.5%) in the propensity-matched cohorts. The adjusted odds ratio for the high-volume hospitals compared with low-volume hospitals was 1.506 (95% confidence interval, 0.875-2.592) for poor neurologic outcome. Higher TTM case volume was significantly associated with early initiation of TTM and lower incidence of adverse events. However, case volume had no association with neurologic outcome and inhospital mortality. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Advanced Concept Exploration for Fast Ignition Science Program, Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stephens, Richard Burnite; McLean, Harry M.; Theobald, Wolfgang

    The Fast Ignition (FI) Concept for Inertial Confinement Fusion (ICF) has the potential to provide a significant advance in the technical attractiveness of Inertial Fusion Energy reactors. FI differs from conventional “central hot spot” (CHS) target ignition by decoupling compression from heating: using a laser (or heavy ion beam or Z pinch) drive pulse (10’s of nanoseconds) to create a dense fuel and a second, much shorter (~10 picoseconds) high intensity pulse to ignite a small volume within the dense fuel. The physics of fast ignition process was the focus of our Advanced Concept Exploration (ACE) program. Ignition depends criticallymore » on two major issues involving Relativistic High Energy Density (RHED) physics: The laser-induced creation of fast electrons and their propagation in high-density plasmas. Our program has developed new experimental platforms, diagnostic packages, computer modeling analyses, and taken advantage of the increasing energy available at laser facilities to advance understanding of the fundamental physics underlying these issues. Our program had three thrust areas: • Understand the production and characteristics of fast electrons resulting from FI relevant laser-plasma interactions and their dependence on laser prepulse and laser pulse length. • Investigate the subsequent fast electron transport in solid and through hot (FI-relevant) plasmas. • Conduct and understand integrated core-heating experiments by comparison to simulations. Over the whole period of this project (three years for this contract), we have greatly advanced our fundamental understanding of the underlying properties in all three areas: • Comprehensive studies on fast electron source characteristics have shown that they are controlled by the laser intensity distribution and the topology and plasma density gradient. Laser pre-pulse induced pre-plasma in front of a solid surface results in increased stand-off distances from the electron origin to the high

  3. Liquid metal fast breeder reactors, 1972--1973

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1974-01-01

    Reference to 1467 publications on liquid sodium fast breeder reactors cited in Nuclear Science Abstracts Volume 26 (1972) through Volume 27 (1973 through June) are contained in this citation to provide information on the contents of the document. References are arranged in order by the original NSA abstract number which approximately places them in chronological order. Sequence numbers appear beside each reference, and the personal author index refers to these sequence numbers. The subject index refers to the original abstract numbers. (auth)

  4. Planning magnetic resonance imaging for prostate cancer intensity-modulated radiation therapy: Impact on target volumes, radiotherapy dose and androgen deprivation administration.

    PubMed

    Horsley, Patrick J; Aherne, Noel J; Edwards, Grace V; Benjamin, Linus C; Wilcox, Shea W; McLachlan, Craig S; Assareh, Hassan; Welshman, Richard; McKay, Michael J; Shakespeare, Thomas P

    2015-03-01

    Magnetic resonance imaging (MRI) scans are increasingly utilized for radiotherapy planning to contour the primary tumors of patients undergoing intensity-modulated radiation therapy (IMRT). These scans may also demonstrate cancer extent and may affect the treatment plan. We assessed the impact of planning MRI detection of extracapsular extension, seminal vesicle invasion, or adjacent organ invasion on the staging, target volume delineation, doses, and hormonal therapy of patients with prostate cancer undergoing IMRT. The records of 509 consecutive patients with planning MRI scans being treated with IMRT for prostate cancer between January 2010 and July 2012 were retrospectively reviewed. Tumor staging and treatment plans before and after MRI were compared. Of the 509 patients, 103 (20%) were upstaged and 44 (9%) were migrated to a higher risk category as a result of findings at MRI. In 94 of 509 patients (18%), the MRI findings altered management. Ninety-four of 509 patients (18%) had a change to their clinical target volume (CTV) or treatment technique, and in 41 of 509 patients (8%) the duration of hormone therapy was changed because of MRI findings. The use of radiotherapy planning MRI altered CTV design, dose and/or duration of androgen deprivation in 18% of patients in this large, single institution series of men planned for dose-escalated prostate IMRT. This has substantial implications for radiotherapy target volumes and doses, as well as duration of androgen deprivation. Further research is required to investigate whether newer MRI techniques can simultaneously fulfill staging and radiotherapy contouring roles. © 2014 Wiley Publishing Asia Pty Ltd.

  5. Target volume and artifact evaluation of a new data-driven 4D CT.

    PubMed

    Martin, Rachael; Pan, Tinsu

    Four-dimensional computed tomography (4D CT) is often used to define the internal gross target volume (IGTV) for radiation therapy of lung cancer. Traditionally, this technique requires the use of an external motion surrogate; however, a new image, data-driven 4D CT, has become available. This study aims to describe this data-driven 4D CT and compare target contours created with it to those created using standard 4D CT. Cine CT data of 35 patients undergoing stereotactic body radiation therapy were collected and sorted into phases using standard and data-driven 4D CT. IGTV contours were drawn using a semiautomated method on maximum intensity projection images of both 4D CT methods. Errors resulting from reproducibility of the method were characterized. A comparison of phase image artifacts was made using a normalized cross-correlation method that assigned a score from +1 (data-driven "better") to -1 (standard "better"). The volume difference between the data-driven and standard IGTVs was not significant (data driven was 2.1 ± 1.0% smaller, P = .08). The Dice similarity coefficient showed good similarity between the contours (0.949 ± 0.006). The mean surface separation was 0.4 ± 0.1 mm and the Hausdorff distance was 3.1 ± 0.4 mm. An average artifact score of +0.37 indicated that the data-driven method had significantly fewer and/or less severe artifacts than the standard method (P = 1.5 × 10 -5 for difference from 0). On average, the difference between IGTVs derived from data-driven and standard 4D CT was not clinically relevant or statistically significant, suggesting data-driven 4D CT can be used in place of standard 4D CT without adjustments to IGTVs. The relatively large differences in some patients were usually attributed to limitations in automatic contouring or differences in artifacts. Artifact reduction and setup simplicity suggest a clinical advantage to data-driven 4D CT. Published by Elsevier Inc.

  6. Technology transfer from NASA to targeted industries, volume 2

    NASA Technical Reports Server (NTRS)

    Mccain, Wayne; Schroer, Bernard J.; Souder, William E.; Spann, Mary S.; Watters, Harry; Ziemke, M. Carl

    1993-01-01

    This volume contains the following materials to support Volume 1: (1) Survey of Metal Fabrication Industry in Alabama; (2) Survey of Electronics Manufacturing/Assembly Industry in Alabama; (3) Apparel Modular Manufacturing Simulators; (4) Synopsis of a Stereolithography Project; (5) Transferring Modular Manufacturing Technology to an Apparel Firm; (6) Letters of Support; (7) Fact Sheets; (8) Publications; and (9) One Stop Access to NASA Technology Brochure.

  7. The Development of a 3D LADAR Simulator Based on a Fast Target Impulse Response Generation Approach

    NASA Astrophysics Data System (ADS)

    Al-Temeemy, Ali Adnan

    2017-09-01

    A new laser detection and ranging (LADAR) simulator has been developed, using MATLAB and its graphical user interface, to simulate direct detection time of flight LADAR systems, and to produce 3D simulated scanning images under a wide variety of conditions. This simulator models each stage from the laser source to data generation and can be considered as an efficient simulation tool to use when developing LADAR systems and their data processing algorithms. The novel approach proposed for this simulator is to generate the actual target impulse response. This approach is fast and able to deal with high scanning requirements without losing the fidelity that accompanies increments in speed. This leads to a more efficient LADAR simulator and opens up the possibility for simulating LADAR beam propagation more accurately by using a large number of laser footprint samples. The approach is to select only the parts of the target that lie in the laser beam angular field by mathematically deriving the required equations and calculating the target angular ranges. The performance of the new simulator has been evaluated under different scanning conditions, the results showing significant increments in processing speeds in comparison to conventional approaches, which are also used in this study as a point of comparison for the results. The results also show the simulator's ability to simulate phenomena related to the scanning process, for example, type of noise, scanning resolution and laser beam width.

  8. Sodium in commonly consumed fast foods in New Zealand: a public health opportunity.

    PubMed

    Prentice, Celia A; Smith, Claire; McLean, Rachael M

    2016-04-01

    (i) To determine the Na content of commonly consumed fast foods in New Zealand and (ii) to estimate Na intake from savoury fast foods for the New Zealand adult population. Commonly consumed fast foods were identified from the 2008/09 New Zealand Adult Nutrition Survey. Na values from all savoury fast foods from chain restaurants (n 471) were obtained from nutrition information on company websites, while the twelve most popular fast-food types from independent outlets (n 52) were determined using laboratory analysis. Results were compared with the UK Food Standards Agency 2012 sodium targets. Nutrient analysis was completed to estimate Na intake from savoury fast foods for the New Zealand population using the 2008/09 New Zealand Adult Nutrition Survey. New Zealand. Adults aged 15 years and above. From chain restaurants, sauces/salad dressings and fried chicken had the highest Na content (per 100 g) and from independent outlets, sausage rolls, battered hotdogs and mince and cheese pies were highest in Na (per 100 g). The majority of fast foods exceeded the UK Food Standards Agency 2012 sodium targets. The mean daily Na intake from savoury fast foods was 283 mg/d for the total adult population and 1229 mg/d for fast-food consumers. Taking into account the Na content and frequency of consumption, potato dishes, filled rolls, hamburgers and battered fish contributed substantially to Na intake for fast-food consumers in New Zealand. These foods should be targeted for Na reduction reformulation.

  9. Evaluation of implementation of fasting guidelines for enterally fed critical care patients.

    PubMed

    Jenkins, Bethan; Calder, Philip C; Marino, Luise V

    2018-02-15

    Critically ill adults have increased nutrition risk. Prior to procedures patients are often fasted, leading to nutritional deficits. The use of fasting guidelines may therefore help reduce deficits from accumulating. The aim of this work was to determine the impact on nutrition support delivery following the implementation of fasting guidelines in addition to characterizing staff knowledge of the guidelines. Retrospective data were collected on n = 74 patients at two different time points; prior to launch of fasting guidelines and post launch, with regards to estimated nutritional requirements, nutritional targets, volume of enteral nutrition (EN) delivered and periods of fasting. Clinical variables of interest were collected for up to 14 days. Questionnaires assessing staff knowledge/barriers to usage of the fasting guidelines were administered to ICU staff. 3 ICUs (General, Cardiac and Neurosciences) within University Hospital Southampton NHS Foundation Trust. Mechanically ventilated adults in an ICU and receiving exclusive EN. Comparison was made between pre- and post-guideline implementation with statistically significant improvements in the % EN delivered (76.4 ± 11.8 vs. 84.1 ± 10.8 (p = 0.0009)) and duration of feeds withheld (41.5 ± 26.6 vs. 27.6 ± 20.8 h (p = 0.02)). There were non-significant improvements pre- and post-implementation in the % of energy and protein delivered (80.7 ± 16.4 vs. 86.5 ± 17.3 (p = 0.15 (NS)); 74 ± 18.3 vs. 79 ± 18.5 (p = 0.15 (NS))). 77% of staff were familiar with the guidelines, whilst 42% requested further education. The main barriers to guideline compliance were delays and unpredictable timing of procedures, and differing guidance from senior staff and non-ICU teams. Implementation of fasting guidelines led to significant improvements in EN delivery and reduced duration of feed breaks. The use of fasting guidelines is a positive step towards increasing nutrition delivery in the ICU. Further

  10. Will weight loss cause significant dosimetric changes of target volumes and organs at risk in nasopharyngeal carcinoma treated with intensity-modulated radiation therapy?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Chuanben; Fei, Zhaodong; Chen, Lisha

    This study aimed to quantify dosimetric effects of weight loss for nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). Overall, 25 patients with NPC treated with IMRT were enrolled. We simulated weight loss during IMRT on the computer. Weight loss model was based on the planning computed tomography (CT) images. The original external contour of head and neck was labeled plan 0, and its volume was regarded as pretreatment normal weight. We shrank the external contour with different margins (2, 3, and 5 mm) and generated new external contours of head and neck. The volumes of reconstructed external contoursmore » were regarded as weight during radiotherapy. After recontouring outlines, the initial treatment plan was mapped to the redefined CT scans with the same beam configurations, yielding new plans. The computer model represented a theoretical proportional weight loss of 3.4% to 13.7% during the course of IMRT. The dose delivered to the planning target volume (PTV) of primary gross tumor volume and clinical target volume significantly increased by 1.9% to 2.9% and 1.8% to 2.9% because of weight loss, respectively. The dose to the PTV of gross tumor volume of lymph nodes fluctuated from −2.0% to 1.0%. The dose to the brain stem and the spinal cord was increased (p < 0.001), whereas the dose to the parotid gland was decreased (p < 0.001). Weight loss may lead to significant dosimetric change during IMRT. Repeated scanning and replanning for patients with NPC with an obvious weight loss may be necessary.« less

  11. Delineation of clinical target volume for postoperative radiotherapy in stage IIIA-pN2 non-small-cell lung cancer

    PubMed Central

    Jing, Xuquan; Meng, Xue; Sun, Xindong; Yu, Jinming

    2016-01-01

    With the high locoregional relapse rate and the improvement of radiation technology, postoperative radiotherapy (PORT) has been widely used in the treatment of completely resected stage IIIA-pN2 non-small-cell lung cancer (NSCLC). However, there is still no definitive consensus on clinical target volume for the pN2 subgroup. This review will discuss how to delineate the clinical target volume (CTV) for pN2 subgroups of IIIA-N2 NSCLC based on the published literature and to investigate the optimal PORT CTV in this cohort of patients. Besides overall survival (OS), locoregional recurrence (LR), and radiotherapy-related toxicity of this subset of the population in the modern PORT era, selection of proper patients will also be considered in this review. In summary, it is appropriate to include involved lymph node stations and uninvolved stations at high risk in PORT CTV for patients with pN2 disease when PORT is administered. PORT can reduce LR and has the potential to improve OS. In the current era of modern radiation technology, PORT can be administered safely with well-tolerated toxicity. Clinicopathological characteristics may be helpful in selecting proper candidates for PORT. PMID:26929651

  12. Delineation of clinical target volume for postoperative radiotherapy in stage IIIA-pN2 non-small-cell lung cancer.

    PubMed

    Jing, Xuquan; Meng, Xue; Sun, Xindong; Yu, Jinming

    2016-01-01

    With the high locoregional relapse rate and the improvement of radiation technology, postoperative radiotherapy (PORT) has been widely used in the treatment of completely resected stage IIIA-pN2 non-small-cell lung cancer (NSCLC). However, there is still no definitive consensus on clinical target volume for the pN2 subgroup. This review will discuss how to delineate the clinical target volume (CTV) for pN2 subgroups of IIIA-N2 NSCLC based on the published literature and to investigate the optimal PORT CTV in this cohort of patients. Besides overall survival (OS), locoregional recurrence (LR), and radiotherapy-related toxicity of this subset of the population in the modern PORT era, selection of proper patients will also be considered in this review. In summary, it is appropriate to include involved lymph node stations and uninvolved stations at high risk in PORT CTV for patients with pN2 disease when PORT is administered. PORT can reduce LR and has the potential to improve OS. In the current era of modern radiation technology, PORT can be administered safely with well-tolerated toxicity. Clinicopathological characteristics may be helpful in selecting proper candidates for PORT.

  13. Pakistan needs to speed up its human immunodeficiency virus control strategy to achieve targets in fast-track acquired immune deficiency syndrome response.

    PubMed

    Waheed, Yasir; Waheed, Hasnain

    2017-05-12

    In last fifteen years remarkable success in the fight against human immunodeficiency virus (HIV) is achieved globally. The number of HIV infections has decreased and the number of people on antiretroviral therapy is increased. This all is possible by strong political commitments and heavy investments in the fight against HIV. Pakistan is among few Asian countries in which HIV cases are increasing year by year since 1990. There are 94000 cases of HIV in Pakistan and only 14000 are registered with government. The main source of HIV infection in Pakistan is the use of contaminated injection equipment among people who inject drugs (PWID). The overall prevalence of HIV among PWID in Pakistan is 27.2%. There are five cities in Pakistan in which HIV prevalence is above 40% in PWIDs. In June 2016, United Nations political declaration on acquired immune deficiency syndrome (AIDS) provided a global mandate to fast-track the AIDS response over the next five years to achieve the targets in Sustainable Development Goals. To achieve the targets in fast-track AIDS response, the global leaders showed strong commitments to invest $ 26 billion per year by 2020. Pakistan needs to speed up its HIV control program. There is a dire need to locate all HIV positive people and enroll them in the treatment program. Pakistan also needs to calculate exact number of people living with HIV, increase HIV treatment centers and increase HIV awareness. Recently, Global Fund invested handsome money in the fight against HIV. Let's hope the country will have effective HIV control strategy to achieve the HIV elimination target by 2030.

  14. High volume fabrication of laser targets using MEMS techniques

    NASA Astrophysics Data System (ADS)

    Spindloe, C.; Arthur, G.; Hall, F.; Tomlinson, S.; Potter, R.; Kar, S.; Green, J.; Higginbotham, A.; Booth, N.; Tolley, M. K.

    2016-04-01

    The latest techniques for the fabrication of high power laser targets, using processes developed for the manufacture of Micro-Electro-Mechanical System (MEMS) devices are discussed. These laser targets are designed to meet the needs of the increased shot numbers that are available in the latest design of laser facilities. Traditionally laser targets have been fabricated using conventional machining or coarse etching processes and have been produced in quantities of 10s to low 100s. Such targets can be used for high complexity experiments such as Inertial Fusion Energy (IFE) studies and can have many complex components that need assembling and characterisation with high precision. Using the techniques that are common to MEMS devices and integrating these with an existing target fabrication capability we are able to manufacture and deliver targets to these systems. It also enables us to manufacture novel targets that have not been possible using other techniques. In addition, developments in the positioning systems that are required to deliver these targets to the laser focus are also required and a system to deliver the target to a focus of an F2 beam at 0.1Hz is discussed.

  15. Delineation of Supraclavicular Target Volumes in Breast Cancer Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, Lindsay C.; Diehn, Felix E.; Boughey, Judy C.

    Purpose: To map the location of gross supraclavicular metastases in patients with breast cancer, in order to determine areas at highest risk of harboring subclinical disease. Methods and Materials: Patients with axial imaging of gross supraclavicular disease were identified from an institutional breast cancer registry. Locations of the metastatic lymph nodes were transferred onto representative axial computed tomography images of the supraclavicular region and compared with the Radiation Therapy Oncology Group (RTOG) breast cancer atlas for radiation therapy planning. Results: Sixty-two patients with 161 supraclavicular nodal metastases were eligible for study inclusion. At the time of diagnosis, 117 nodal metastasesmore » were present in 44 patients. Forty-four nodal metastases in 18 patients were detected at disease recurrence, 4 of whom had received prior radiation to the supraclavicular fossa. Of the 161 nodal metastases, 95 (59%) were within the RTOG consensus volume, 4 nodal metastases (2%) in 3 patients were marginally within the volume, and 62 nodal metastases (39%) in 30 patients were outside the volume. Supraclavicular disease outside the RTOG consensus volume was located in 3 regions: at the level of the cricoid and thyroid cartilage (superior to the RTOG volume), in the posterolateral supraclavicular fossa (posterolateral to the RTOG volume), and in the lateral low supraclavicular fossa (lateral to the RTOG volume). Only women with multiple supraclavicular metastases had nodal disease that extended superiorly to the level of the thyroid cartilage. Conclusions: For women with risk of harboring subclinical supraclavicular disease warranting the addition of supraclavicular radiation, coverage of the posterior triangle and the lateral low supraclavicular region should be considered. For women with known supraclavicular disease, extension of neck coverage superior to the cricoid cartilage may be warranted.« less

  16. Homogeneous fast-flux isotope-production reactor

    DOEpatents

    Cawley, W.E.; Omberg, R.P.

    1982-08-19

    A method is described for producing tritium in a liquid metal fast breeder reactor. Lithium target material is dissolved in the liquid metal coolant in order to facilitate the production and removal of tritium.

  17. Estimation of error in maximal intensity projection-based internal target volume of lung tumors: a simulation and comparison study using dynamic magnetic resonance imaging.

    PubMed

    Cai, Jing; Read, Paul W; Baisden, Joseph M; Larner, James M; Benedict, Stanley H; Sheng, Ke

    2007-11-01

    To evaluate the error in four-dimensional computed tomography (4D-CT) maximal intensity projection (MIP)-based lung tumor internal target volume determination using a simulation method based on dynamic magnetic resonance imaging (dMRI). Eight healthy volunteers and six lung tumor patients underwent a 5-min MRI scan in the sagittal plane to acquire dynamic images of lung motion. A MATLAB program was written to generate re-sorted dMRI using 4D-CT acquisition methods (RedCAM) by segmenting and rebinning the MRI scans. The maximal intensity projection images were generated from RedCAM and dMRI, and the errors in the MIP-based internal target area (ITA) from RedCAM (epsilon), compared with those from dMRI, were determined and correlated with the subjects' respiratory variability (nu). Maximal intensity projection-based ITAs from RedCAM were comparatively smaller than those from dMRI in both phantom studies (epsilon = -21.64% +/- 8.23%) and lung tumor patient studies (epsilon = -20.31% +/- 11.36%). The errors in MIP-based ITA from RedCAM correlated linearly (epsilon = -5.13nu - 6.71, r(2) = 0.76) with the subjects' respiratory variability. Because of the low temporal resolution and retrospective re-sorting, 4D-CT might not accurately depict the excursion of a moving tumor. Using a 4D-CT MIP image to define the internal target volume might therefore cause underdosing and an increased risk of subsequent treatment failure. Patient-specific respiratory variability might also be a useful predictor of the 4D-CT-induced error in MIP-based internal target volume determination.

  18. High-power liquid-lithium jet target for neutron production

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Halfon, S.; Feinberg, G.; Racah Institute of Physics, Hebrew University, Jerusalem 91904

    2013-12-15

    A compact liquid-lithium target (LiLiT) was built and tested with a high-power electron gun at the Soreq Nuclear Research Center. The lithium target, to be bombarded by the high-intensity proton beam of the Soreq Applied Research Accelerator Facility (SARAF), will constitute an intense source of neutrons produced by the {sup 7}Li(p,n){sup 7}Be reaction for nuclear astrophysics research and as a pilot setup for accelerator-based Boron Neutron Capture Therapy. The liquid-lithium jet target acts both as neutron-producing target and beam dump by removing the beam thermal power (>5 kW, >1 MW/cm{sup 3}) with fast transport. The target was designed based onmore » a thermal model, accompanied by a detailed calculation of the {sup 7}Li(p,n) neutron yield, energy distribution, and angular distribution. Liquid lithium is circulated through the target loop at ∼200 °C and generates a stable 1.5 mm-thick film flowing at a velocity up to 7 m/s onto a concave supporting wall. Electron beam irradiation demonstrated that the liquid-lithium target can dissipate electron power areal densities of >4 kW/cm{sup 2} and volume power density of ∼2 MW/cm{sup 3} at a lithium flow of ∼4 m/s while maintaining stable temperature and vacuum conditions. The LiLiT setup is presently in online commissioning stage for high-intensity proton beam irradiation (1.91–2.5 MeV, 1–2 mA) at SARAF.« less

  19. Tetrafluoroethane (R134a) hydrate formation within variable volume reactor accompanied by evaporation and condensation.

    PubMed

    Jeong, K; Choo, Y S; Hong, H J; Yoon, Y S; Song, M H

    2015-03-01

    Vast size hydrate formation reactors with fast conversion rate are required for the economic implementation of seawater desalination utilizing gas hydrate technology. The commercial target production rate is order of thousand tons of potable water per day per train. Various heat and mass transfer enhancement schemes including agitation, spraying, and bubbling have been examined to maximize the production capacities in scaled up design of hydrate formation reactors. The present experimental study focused on acquiring basic knowledge needed to design variable volume reactors to produce tetrafluoroethane hydrate slurry. Test vessel was composed of main cavity with fixed volume of 140 ml and auxiliary cavity with variable volume of 0 ∼ 64 ml. Temperatures at multiple locations within vessel and pressure were monitored while visual access was made through front window. Alternating evaporation and condensation induced by cyclic volume change provided agitation due to density differences among water and vapor, liquid and hydrate R134a as well as extended interface area, which improved hydrate formation kinetics coupled with latent heat release and absorption. Influences of coolant temperature, piston stroke/speed, and volume change period on hydrate formation kinetics were investigated. Suggestions of reactor design improvement for future experimental study are also made.

  20. Tetrafluoroethane (R134a) hydrate formation within variable volume reactor accompanied by evaporation and condensation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeong, K.; Choo, Y. S.; Hong, H. J.

    Vast size hydrate formation reactors with fast conversion rate are required for the economic implementation of seawater desalination utilizing gas hydrate technology. The commercial target production rate is order of thousand tons of potable water per day per train. Various heat and mass transfer enhancement schemes including agitation, spraying, and bubbling have been examined to maximize the production capacities in scaled up design of hydrate formation reactors. The present experimental study focused on acquiring basic knowledge needed to design variable volume reactors to produce tetrafluoroethane hydrate slurry. Test vessel was composed of main cavity with fixed volume of 140 mlmore » and auxiliary cavity with variable volume of 0 ∼ 64 ml. Temperatures at multiple locations within vessel and pressure were monitored while visual access was made through front window. Alternating evaporation and condensation induced by cyclic volume change provided agitation due to density differences among water and vapor, liquid and hydrate R134a as well as extended interface area, which improved hydrate formation kinetics coupled with latent heat release and absorption. Influences of coolant temperature, piston stroke/speed, and volume change period on hydrate formation kinetics were investigated. Suggestions of reactor design improvement for future experimental study are also made.« less

  1. Influence of field ionization effect on the divergence of laser-driven fast electrons

    NASA Astrophysics Data System (ADS)

    Lang, Y.; Yang, X. H.; Xu, H.; Jin, Z.; Zhuo, H. B.

    2018-07-01

    The effect of field ionization on the divergence of fast electrons (E k ≥ 50 keV), driven by ultrashort-ultraintense laser pulse interaction with plasma, is studied by using 2D3V particle-in-cell simulations. It is found that, due to temperature anisotropy of the fast electrons in the ionizing target, strong fluctuant magnetic fields in the preplasma region is generated through Weibel instability. In turn, the field induces an enhancement of the hot electron divergence for the target with ionization process. Meanwhile, compared with the target without an ionization process, larger divergence of hot electrons can also be seen in the ionizing target with laser intensity varying from 5 × 1019 W/cm2 to 5 × 1020 W/cm2 and the divergence is weakly dependent on target materials for a fixed profile of preplasma. The results here are useful for the application of laser-driven fast electron beams.

  2. Fusion yield rate recovery by escaping hot-spot fast ions in the neighboring fuel layer

    NASA Astrophysics Data System (ADS)

    Tang, Xian-Zhu; McDevitt, C. J.; Guo, Zehua; Berk, H. L.

    2014-02-01

    Free-streaming loss by fast ions can deplete the tail population in the hot spot of an inertial confinement fusion (ICF) target. Escaping fast ions in the neighboring fuel layer of a cryogenic target can produce a surplus of fast ions locally. In contrast to the Knudsen layer effect that reduces hot-spot fusion reactivity due to tail ion depletion, the inverse Knudsen layer effect increases fusion reactivity in the neighboring fuel layer. In the case of a burning ICF target in the presence of significant hydrodynamic mix which aggravates the Knudsen layer effect, the yield recovery largely compensates for the yield reduction. For mix-dominated sub-ignition targets, the yield reduction is the dominant process.

  3. Large-Scale Off-Target Identification Using Fast and Accurate Dual Regularized One-Class Collaborative Filtering and Its Application to Drug Repurposing.

    PubMed

    Lim, Hansaim; Poleksic, Aleksandar; Yao, Yuan; Tong, Hanghang; He, Di; Zhuang, Luke; Meng, Patrick; Xie, Lei

    2016-10-01

    Target-based screening is one of the major approaches in drug discovery. Besides the intended target, unexpected drug off-target interactions often occur, and many of them have not been recognized and characterized. The off-target interactions can be responsible for either therapeutic or side effects. Thus, identifying the genome-wide off-targets of lead compounds or existing drugs will be critical for designing effective and safe drugs, and providing new opportunities for drug repurposing. Although many computational methods have been developed to predict drug-target interactions, they are either less accurate than the one that we are proposing here or computationally too intensive, thereby limiting their capability for large-scale off-target identification. In addition, the performances of most machine learning based algorithms have been mainly evaluated to predict off-target interactions in the same gene family for hundreds of chemicals. It is not clear how these algorithms perform in terms of detecting off-targets across gene families on a proteome scale. Here, we are presenting a fast and accurate off-target prediction method, REMAP, which is based on a dual regularized one-class collaborative filtering algorithm, to explore continuous chemical space, protein space, and their interactome on a large scale. When tested in a reliable, extensive, and cross-gene family benchmark, REMAP outperforms the state-of-the-art methods. Furthermore, REMAP is highly scalable. It can screen a dataset of 200 thousands chemicals against 20 thousands proteins within 2 hours. Using the reconstructed genome-wide target profile as the fingerprint of a chemical compound, we predicted that seven FDA-approved drugs can be repurposed as novel anti-cancer therapies. The anti-cancer activity of six of them is supported by experimental evidences. Thus, REMAP is a valuable addition to the existing in silico toolbox for drug target identification, drug repurposing, phenotypic screening, and

  4. Large-Scale Off-Target Identification Using Fast and Accurate Dual Regularized One-Class Collaborative Filtering and Its Application to Drug Repurposing

    PubMed Central

    Poleksic, Aleksandar; Yao, Yuan; Tong, Hanghang; Meng, Patrick; Xie, Lei

    2016-01-01

    Target-based screening is one of the major approaches in drug discovery. Besides the intended target, unexpected drug off-target interactions often occur, and many of them have not been recognized and characterized. The off-target interactions can be responsible for either therapeutic or side effects. Thus, identifying the genome-wide off-targets of lead compounds or existing drugs will be critical for designing effective and safe drugs, and providing new opportunities for drug repurposing. Although many computational methods have been developed to predict drug-target interactions, they are either less accurate than the one that we are proposing here or computationally too intensive, thereby limiting their capability for large-scale off-target identification. In addition, the performances of most machine learning based algorithms have been mainly evaluated to predict off-target interactions in the same gene family for hundreds of chemicals. It is not clear how these algorithms perform in terms of detecting off-targets across gene families on a proteome scale. Here, we are presenting a fast and accurate off-target prediction method, REMAP, which is based on a dual regularized one-class collaborative filtering algorithm, to explore continuous chemical space, protein space, and their interactome on a large scale. When tested in a reliable, extensive, and cross-gene family benchmark, REMAP outperforms the state-of-the-art methods. Furthermore, REMAP is highly scalable. It can screen a dataset of 200 thousands chemicals against 20 thousands proteins within 2 hours. Using the reconstructed genome-wide target profile as the fingerprint of a chemical compound, we predicted that seven FDA-approved drugs can be repurposed as novel anti-cancer therapies. The anti-cancer activity of six of them is supported by experimental evidences. Thus, REMAP is a valuable addition to the existing in silico toolbox for drug target identification, drug repurposing, phenotypic screening, and

  5. Effects of plyometric training volume and training surface on explosive strength.

    PubMed

    Ramírez-Campillo, Rodrigo; Andrade, David C; Izquierdo, Mikel

    2013-10-01

    The purpose of this study is to examine the effects of different volume and training surfaces during a short-term plyometric training program on neuromuscular performance. Twenty-nine subjects were randomly assigned to 4 groups: control group (CG, n = 5), moderate volume group (MVG, n = 9, 780 jumps), moderate volume hard surface group (MVGHS, n = 8, 780 jumps), and high volume group (HVG, n = 7, 1,560 jumps). A series of tests were performed by the subjects before and after 7 weeks of plyometric training. These tests were measurement of maximum strength (5 maximum repetitions [5RMs]), drop jumps (DJs) of varying heights (20, 40, and 60 cm), squat and countermovement jumps (SJ and CMJ, respectively), timed 20-m sprint, agility, body weight, and height. The results of the present study suggest that high training volume leads to a significant increase in explosive performance that requires fast stretch-shortening cycle (SSC) actions (such as DJ and sprint) in comparison to what is observed after a moderate training volume regimen. Second, when plyometric training is performed on a hard training surface (high-impact reaction force), a moderate training volume induces optimal stimulus to increase explosive performance requiring fast SSC actions (e.g., DJ), maximal dynamic strength enhancement, and higher training efficiency. Thus, a finding of interest in the study was that after 7 weeks of plyometric training, performance enhancement in maximal strength and in actions requiring fast SSC (such as DJ and sprint) were dependent on the volume of training and the surface on which it was performed. This must be taken into account when using plyometric training on different surfaces.

  6. Targeted Single-Shot Methods for Diffusion-Weighted Imaging in the Kidneys

    PubMed Central

    Jin, Ning; Deng, Jie; Zhang, Longjiang; Zhang, Zhuoli; Lu, Guangming; Omary, Reed A.; Larson, Andrew C.

    2011-01-01

    Purpose To investigate the feasibility of combining the inner-volume-imaging (IVI) technique with single-shot diffusion-weighted (DW) spin-echo echo-planar imaging (SE-EPI) and DW-SPLICE (split acquisition of fast spin-echo) sequences for renal DW imaging. Materials and Methods Renal DW imaging was performed in 10 healthy volunteers using single-shot DW-SE-EPI, DW-SPLICE, targeted-DW-SE-EPI and targeted-DW-SPLICE. We compared the quantitative diffusion measurement accuracy and image quality of these targeted-DW-SE-EPI and targeted DW-SPLICE methods with conventional full FOV DW-SE-EPI and DW-SPLICE measurements in phantoms and normal volunteers. Results Compared with full FOV DW-SE-EPI and DW-SPLICE methods, targeted-DW-SE-EPI and targeted-DW-SPLICE approaches produced images of superior overall quality with fewer artifacts, less distortion and reduced spatial blurring in both phantom and volunteer studies. The ADC values measured with each of the four methods were similar and in agreement with previously published data. There were no statistically significant differences between the ADC values and intra-voxel incoherent motion (IVIM) measurements in the kidney cortex and medulla using single-shot DW-SE-EPI, targeted-DW-EPI and targeted-DW-SPLICE (p > 0.05). Conclusion Compared with full-FOV DW imaging methods, targeted-DW-SE-EPI and targeted-DW-SPLICE techniques reduced image distortion and artifacts observed in the single-shot DW-SE-EPI images, reduced blurring in DW-SPLICE images and produced comparable quantitative DW and IVIM measurements to those produced with conventional full-FOV approaches. PMID:21591023

  7. Fast approximation for joint optimization of segmentation, shape, and location priors, and its application in gallbladder segmentation.

    PubMed

    Saito, Atsushi; Nawano, Shigeru; Shimizu, Akinobu

    2017-05-01

    This paper addresses joint optimization for segmentation and shape priors, including translation, to overcome inter-subject variability in the location of an organ. Because a simple extension of the previous exact optimization method is too computationally complex, we propose a fast approximation for optimization. The effectiveness of the proposed approximation is validated in the context of gallbladder segmentation from a non-contrast computed tomography (CT) volume. After spatial standardization and estimation of the posterior probability of the target organ, simultaneous optimization of the segmentation, shape, and location priors is performed using a branch-and-bound method. Fast approximation is achieved by combining sampling in the eigenshape space to reduce the number of shape priors and an efficient computational technique for evaluating the lower bound. Performance was evaluated using threefold cross-validation of 27 CT volumes. Optimization in terms of translation of the shape prior significantly improved segmentation performance. The proposed method achieved a result of 0.623 on the Jaccard index in gallbladder segmentation, which is comparable to that of state-of-the-art methods. The computational efficiency of the algorithm is confirmed to be good enough to allow execution on a personal computer. Joint optimization of the segmentation, shape, and location priors was proposed, and it proved to be effective in gallbladder segmentation with high computational efficiency.

  8. Chemoradiation for ductal pancreatic carcinoma: principles of combining chemotherapy with radiation, definition of target volume and radiation dose.

    PubMed

    Wilkowski, Ralf; Thoma, Martin; Weingandt, Helmut; Dühmke, Eckhart; Heinemann, Volker

    2005-05-10

    Review of the role of chemoradiotherapy in the treatment of locally advanced pancreatic cancer with a specific focus on the technical feasibility and the integration of chemoradiotherapy into multimodal treatment concepts. Combined chemoradiotherapy of pancreatic cancer is a safe treatment with an acceptable profile of side effects when applied with modern planning and radiation techniques as well as considering tissue tolerance. Conventionally fractionated radiation regimens with total doses of 45-50 Gy and small-volume boost radiation with 5.4 Gy have found the greatest acceptance. Locoregional lymphatic drainage should be included in the planning of target volumes because the risk of tumor involvement and local or loco-regional recurrence is high. Up to now, 5-fluorouracil has been considered the "standard" agent for concurrent chemoradiotherapy. The role of gemcitabine given concurrently with radiation has not yet been defined, since high local efficacy may also be accompanied by enhanced toxicities. In addition, no dose or administration form has been determined to be "standard" up to now. The focus of presently ongoing research is to define an effective and feasible regimen of concurrent chemoradiotherapy. While preliminary results indicate promising results using gemcitabine-based chemoradiotherapy, reliable data derived from mature phase III trials are greatly needed. Intensity-modulated radiotherapy has been developed to improve target-specific radiation and to reduce organ toxicity. Its clinical relevance still needs to be defined.

  9. Consequences of additional use of PET information for target volume delineation and radiotherapy dose distribution for esophageal cancer.

    PubMed

    Muijs, Christina T; Schreurs, Liesbeth M; Busz, Dianne M; Beukema, Jannet C; van der Borden, Arnout J; Pruim, Jan; Van der Jagt, Eric J; Plukker, John Th; Langendijk, Johannes A

    2009-12-01

    To determine the consequences of target volume (TV) modifications, based on the additional use of PET information, on radiation planning, assuming PET/CT-imaging represents the true extent of the tumour. For 21 patients with esophageal cancer, two separate TV's were retrospectively defined based on CT (CT-TV) and co-registered PET/CT images (PET/CT-TV). Two 3D-CRT plans (prescribed dose 50.4 Gy) were constructed to cover the corresponding TV's. Subsequently, these plans were compared for target coverage, normal tissue dose-volume histograms and the corresponding normal tissue complication probability (NTCP) values. The addition of PET led to the modification of CT-TV with at least 10% in 12 of 21 patients (57%) (reduction in 9, enlargement in 3). PET/CT-TV was inadequately covered by the CT-based treatment plan in 8 patients (36%). Treatment plan modifications resulted in significant changes (p<0.05) in dose distributions to heart and lungs. Corresponding changes in NTCP values ranged from -3% to +2% for radiation pneumonitis and from -0.2% to +1.2% for cardiac mortality. This study demonstrated that TV's based on CT might exclude PET-avid disease. Consequences are under dosing and thereby possibly ineffective treatment. Moreover, the addition of PET in radiation planning might result in clinical important changes in NTCP.

  10. Estimation of Error in Maximal Intensity Projection-Based Internal Target Volume of Lung Tumors: A Simulation and Comparison Study Using Dynamic Magnetic Resonance Imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cai Jing; Read, Paul W.; Baisden, Joseph M.

    Purpose: To evaluate the error in four-dimensional computed tomography (4D-CT) maximal intensity projection (MIP)-based lung tumor internal target volume determination using a simulation method based on dynamic magnetic resonance imaging (dMRI). Methods and Materials: Eight healthy volunteers and six lung tumor patients underwent a 5-min MRI scan in the sagittal plane to acquire dynamic images of lung motion. A MATLAB program was written to generate re-sorted dMRI using 4D-CT acquisition methods (RedCAM) by segmenting and rebinning the MRI scans. The maximal intensity projection images were generated from RedCAM and dMRI, and the errors in the MIP-based internal target area (ITA)more » from RedCAM ({epsilon}), compared with those from dMRI, were determined and correlated with the subjects' respiratory variability ({nu}). Results: Maximal intensity projection-based ITAs from RedCAM were comparatively smaller than those from dMRI in both phantom studies ({epsilon} = -21.64% {+-} 8.23%) and lung tumor patient studies ({epsilon} = -20.31% {+-} 11.36%). The errors in MIP-based ITA from RedCAM correlated linearly ({epsilon} = -5.13{nu} - 6.71, r{sup 2} = 0.76) with the subjects' respiratory variability. Conclusions: Because of the low temporal resolution and retrospective re-sorting, 4D-CT might not accurately depict the excursion of a moving tumor. Using a 4D-CT MIP image to define the internal target volume might therefore cause underdosing and an increased risk of subsequent treatment failure. Patient-specific respiratory variability might also be a useful predictor of the 4D-CT-induced error in MIP-based internal target volume determination.« less

  11. Device and method for imploding a microsphere with a fast liner

    DOEpatents

    Thode, Lester E.

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner to drive the fast liner to implode a microsphere.

  12. Polarization of fast particle beams by collisional pumping

    DOEpatents

    Stearns, J.W.; Kaplan, S.N.; Pyle, R.V.; Anderson, L.W.; Schlachter, A.S.; Ruby, L.

    1984-10-19

    The invention relates to method and apparatus for polarizing a fast beam of particles by collisional pumping, including generating a fast beam of particles, and generating a thick electron-spin-polarized medium positioned as a target for said beam, said medium being sufficiently thick to allow said beam to interact with said medium to produce collisional pumping whereby said particle beam becomes highly polarized.

  13. Epigenetic-Imprinting Changes Caused by Neonatal Fasting Stress Protect From Future Fasting Stress.

    PubMed

    Jiang, Y; Denbow, C; Meiri, N; Denbow, D M

    2016-01-01

    Unfavourable nutritional conditions during the neonatal critical period can cause both acute metabolic disorders and severe metabolic syndromes in later life. These phenomena have been tightly related to the epigenetic modification controlling the balance between satiety and hunger in the hypothalamus. In the present study, we investigated epigenetic modification associated with both the fasting stress effects and the short-term resilience to fasting stress in the hypothalamic paraventricular nucleus (PVN) of chicks. Fasting for 24 h at 3 days of age (D) (i.e. D3) significantly increased global methylation at lysine 27 of histone 3 (H3K27) and its specific histone methyltransferase (HMT) expression level in the PVN. Because global methylation could not fully reveal the changes at specific genes, the regulation of the gene for brain-derived neurotrophic factor (Bdnf), which was recently also found to have an anorexigenic effect, was evaluated as a potential target. Chromatin immunoprecipitation assay analysis revealed that tri- (me3) and di-methylated (me2) H3K27 exhibited an instant (on D4 only) and latent increase (on both D11 and D41), respectively, at the putative promoter of Bdnf after 24 h of fasting on D3. This indicated that fasting could regulate energy-expenditure-related genes via modifying methylation at H3K27, which we suspected might be a protective mechanism for keeping the inner environment homeostatic. To test this hypothesis, a short-term repetitive fasting stress was applied to chickens, which were fasted for 24 h either on D10 only or on both D3 and D10. It was found that pre-existing fasting on D3 could induce a short-term fasting resilience, which rescued the reduction of Bdnf expression from future fasting on D10. We call this phenomenon the ‘molecular memory’, which was mainly conducted by HMTs and H3K27me2/me3 in the PVN. In conclusion, chicks respond to fasting with dynamic methylation at H3K27 in the PVN during the neonatal critical

  14. Robust, active tumor-targeting and fast bioresponsive anticancer nanotherapeutics based on natural endogenous materials.

    PubMed

    Sun, Bingfeng; Deng, Chao; Meng, Fenghua; Zhang, Jian; Zhong, Zhiyuan

    2016-11-01

    The clinical success of cancer nanomedicines critically depends on availability of simple, safe and highly efficient nanocarriers. Here, we report that robust and multifunctional nanoparticles self-assembled from hyaluronic acid-g-poly(γ-benzyl-l-glutamate)-lipoic acid conjugates achieve a remarkably high loading (up to 25.8wt.%) and active targeted delivery of doxorubicin (DOX) to human breast tumor xenograft in vivo. DOX-loaded nanoparticles following auto-crosslinking (DOX-CLNPs) are highly stable with little drug leakage under physiological conditions while quickly release ca. 92% DOX in 30h under a cytoplasmic-mimicking reductive environment. The in vitro assays reveal that DOX-CLNPs possess a superior selectivity and antitumor activity to clinically used pegylated liposomal doxorubicin hydrochloride (DOX-LPs) in CD44 receptor overexpressing MCF-7 human breast cancer cells. Strikingly, DOX-CLNPs exhibit a superb tolerated dose of over 100mg DOX equiv./kg, which is more than 5 times higher than DOX-LPs, and an extraordinary breast tumor accumulation of 8.6%ID/g in mice. The in vivo therapeutic studies in MCF-7 human breast tumor-bearing nude mice show that DOX-CLNPs effectively inhibit tumor growth, improve survival rate, and significantly decrease adverse effects as compared to DOX-LPs. DOX-CLNPs based on natural endogenous materials with high drug loading, great stability and CD44-targetability are highly promising for precision cancer chemotherapy. We demonstrate that with rational design, simple and multifunctional anticancer nanotherapeutics can be developed to achieve highly efficient and targeted cancer chemotherapy. Doxorubicin-loaded multifunctional nanoparticles based on hyaluronic acid-g-poly(γ-benzyl-l-glutamate)-lipoic acid conjugates exhibit a high drug loading, superior stability, fast bioresponsivity, high tolerability, and obvious selectivity toward CD44-overexpressing tumors in vivo. These nanotherapeutics achieve effective tumor suppression

  15. Sci—Fri AM: Mountain — 06: Optimizing planning target volume in lung radiotherapy using deformable registration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoang, P; Wierzbicki, M; Juravinski Cancer Centre, Medical Physics Department, Hamilton, Ontario

    A four dimensional computed tomography (4DCT) image is acquired for all radically treated, lung cancer patients to define the internal target volume (ITV), which encompasses tumour motion due to breathing and subclinical disease. Patient set-up error and anatomical motion that is not due to breathing is addressed through an additional 1 cm margin around the ITV to obtain the planning target volume (PTV). The objective of this retrospective study is to find the minimum PTV margin that provides an acceptable probability of delivering the prescribed dose to the ITV. Acquisition of a kV cone beam computed tomography (CBCT) image atmore » each fraction was used to shift the treatment couch to accurately align the spinal cord and carina. Our method utilized deformable image registration to automatically position the planning ITV on each CBCT. We evaluated the percentage of the ITV surface that fell within various PTVs for 79 fractions across 18 patients. Treatment success was defined as a situation where at least 99% of the ITV is covered by the PTV. Overall, this is to be achieved in at least 90% of the treatment fractions. The current approach with a 1cm PTV margin was successful ∼96% of the time. This analysis revealed that the current margin can be reduced to 0.8cm isotropic or 0.6×0.6×1 cm{sup 3} non-isotropic, which were successful 92 and 91 percent of the time respectively. Moreover, we have shown that these margins maintain accuracy, despite intrafractional variation, and maximize CBCT image guidance capabilities.« less

  16. Comparison of Magnetic Resonance Imaging and Computed Tomography for Breast Target Volume Delineation in Prone and Supine Positions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pogson, Elise M.; Liverpool and Macarthur Cancer Therapy Centres, Liverpool; Ingham Institute for Applied Medical Research, Liverpool

    2016-11-15

    Purpose: To determine whether T2-weighted MRI improves seroma cavity (SC) and whole breast (WB) interobserver conformity for radiation therapy purposes, compared with the gold standard of CT, both in the prone and supine positions. Methods and Materials: Eleven observers (2 radiologists and 9 radiation oncologists) delineated SC and WB clinical target volumes (CTVs) on T2-weighted MRI and CT supine and prone scans (4 scans per patient) for 33 patient datasets. Individual observer's volumes were compared using the Dice similarity coefficient, volume overlap index, center of mass shift, and Hausdorff distances. An average cavity visualization score was also determined. Results: Imaging modalitymore » did not affect interobserver variation for WB CTVs. Prone WB CTVs were larger in volume and more conformal than supine CTVs (on both MRI and CT). Seroma cavity volumes were larger on CT than on MRI. Seroma cavity volumes proved to be comparable in interobserver conformity in both modalities (volume overlap index of 0.57 (95% Confidence Interval (CI) 0.54-0.60) for CT supine and 0.52 (95% CI 0.48-0.56) for MRI supine, 0.56 (95% CI 0.53-0.59) for CT prone and 0.55 (95% CI 0.51-0.59) for MRI prone); however, after registering modalities together the intermodality variation (Dice similarity coefficient of 0.41 (95% CI 0.36-0.46) for supine and 0.38 (0.34-0.42) for prone) was larger than the interobserver variability for SC, despite the location typically remaining constant. Conclusions: Magnetic resonance imaging interobserver variation was comparable to CT for the WB CTV and SC delineation, in both prone and supine positions. Although the cavity visualization score and interobserver concordance was not significantly higher for MRI than for CT, the SCs were smaller on MRI, potentially owing to clearer SC definition, especially on T2-weighted MR images.« less

  17. Enabling fast charging - Battery thermal considerations

    NASA Astrophysics Data System (ADS)

    Keyser, Matthew; Pesaran, Ahmad; Li, Qibo; Santhanagopalan, Shriram; Smith, Kandler; Wood, Eric; Ahmed, Shabbir; Bloom, Ira; Dufek, Eric; Shirk, Matthew; Meintz, Andrew; Kreuzer, Cory; Michelbacher, Christopher; Burnham, Andrew; Stephens, Thomas; Francfort, James; Carlson, Barney; Zhang, Jiucai; Vijayagopal, Ram; Hardy, Keith; Dias, Fernando; Mohanpurkar, Manish; Scoffield, Don; Jansen, Andrew N.; Tanim, Tanvir; Markel, Anthony

    2017-11-01

    Battery thermal barriers are reviewed with regards to extreme fast charging. Present-day thermal management systems for battery electric vehicles are inadequate in limiting the maximum temperature rise of the battery during extreme fast charging. If the battery thermal management system is not designed correctly, the temperature of the cells could reach abuse temperatures and potentially send the cells into thermal runaway. Furthermore, the cell and battery interconnect design needs to be improved to meet the lifetime expectations of the consumer. Each of these aspects is explored and addressed as well as outlining where the heat is generated in a cell, the efficiencies of power and energy cells, and what type of battery thermal management solutions are available in today's market. Thermal management is not a limiting condition with regard to extreme fast charging, but many factors need to be addressed especially for future high specific energy density cells to meet U.S. Department of Energy cost and volume goals.

  18. Interpretation of fast-ion signals during beam modulation experiments

    DOE PAGES

    Heidbrink, W. W.; Collins, C. S.; Stagner, L.; ...

    2016-07-22

    Fast-ion signals produced by a modulated neutral beam are used to infer fast-ion transport. The measured quantity is the divergence of perturbed fast-ion flux from the phase-space volume measured by the diagnostic, ∇•more » $$\\bar{Γ}$$. Since velocity-space transport often contributes to this divergence, the phase-space sensitivity of the diagnostic (or “weight function”) plays a crucial role in the interpretation of the signal. The source and sink make major contributions to the signal but their effects are accurately modeled by calculations that employ an exponential decay term for the sink. Recommendations for optimal design of a fast-ion transport experiment are given, illustrated by results from DIII-D measurements of fast-ion transport by Alfv´en eigenmodes. Finally, the signal-to-noise ratio of the diagnostic, systematic uncertainties in the modeling of the source and sink, and the non-linearity of the perturbation all contribute to the error in ∇•$$\\bar{Γ}$$.« less

  19. Fast-ion Dα spectrum diagnostic in the EAST

    NASA Astrophysics Data System (ADS)

    Hou, Y. M.; Wu, C. R.; Huang, J.; Heidbrink, W. W.; von Hellermann, M. G.; Xu, Z.; Jin, Z.; Chang, J. F.; Zhu, Y. B.; Gao, W.; Chen, Y. J.; Lyu, B.; Hu, R. J.; Zhang, P. F.; Zhang, L.; Gao, W.; Wu, Z. W.; Yu, Y.; Ye, M. Y.

    2016-11-01

    In toroidal magnetic fusion devices, fast-ion D-alpha diagnostic (FIDA) is a powerful method to study the fast-ion feature. The fast-ion characteristics can be inferred from the Doppler shifted spectrum of Dα light according to charge exchange recombination process between fast ions and probe beam. Since conceptual design presented in the last HTPD conference, significant progress has been made to apply FIDA systems on the Experimental Advanced Superconducting Tokamak (EAST). Both co-current and counter-current neutral beam injectors are available, and each can deliver 2-4 MW beam power with 50-80 keV beam energy. Presently, two sets of high throughput spectrometer systems have been installed on EAST, allowing to capture passing and trapped fast-ion characteristics simultaneously, using Kaiser HoloSpec transmission grating spectrometer and Bunkoukeiki FLP-200 volume phase holographic spectrometer coupled with Princeton Instruments ProEM 1024B eXcelon and Andor DU-888 iXon3 1024 CCD camera, respectively. This paper will present the details of the hardware descriptions and experimental spectrum.

  20. Integrated simulation of magnetic-field-assist fast ignition laser fusion

    NASA Astrophysics Data System (ADS)

    Johzaki, T.; Nagatomo, H.; Sunahara, A.; Sentoku, Y.; Sakagami, H.; Hata, M.; Taguchi, T.; Mima, K.; Kai, Y.; Ajimi, D.; Isoda, T.; Endo, T.; Yogo, A.; Arikawa, Y.; Fujioka, S.; Shiraga, H.; Azechi, H.

    2017-01-01

    To enhance the core heating efficiency in fast ignition laser fusion, the concept of relativistic electron beam guiding by external magnetic fields was evaluated by integrated simulations for FIREX class targets. For the cone-attached shell target case, the core heating performance deteriorates by applying magnetic fields since the core is considerably deformed and most of the fast electrons are reflected due to the magnetic mirror formed through the implosion. On the other hand, in the case of a cone-attached solid ball target, the implosion is more stable under the kilo-tesla-class magnetic field. In addition, feasible magnetic field configuration is formed through the implosion. As a result, the core heating efficiency doubles by magnetic guiding. The dependence of core heating properties on the heating pulse shot timing was also investigated for the solid ball target.

  1. TU-E-BRA-11: Volume of Interest Cone Beam CT with a Low-Z Linear Accelerator Target: Proof-of-Concept.

    PubMed

    Robar, J; Parsons, D; Berman, A; MacDonald, A

    2012-06-01

    This study demonstrates feasibility and advantages of volume of interest (VOI) cone beam CT (CBCT) imaging performed with an x-ray beam generated from 2.35 MeV electrons incident on a carbon linear accelerator target. The electron beam energy was reduced to 2.35 MeV in a Varian 21EX linear accelerator containing a 7.6 mm thick carbon x-ray target. Arbitrary imaging volumes were defined in the planning system to produce dynamic MLC sequences capable of tracking off-axis VOIs in phantoms. To reduce truncation artefacts, missing data in projection images were completed using a priori DRR information from the planning CT set. The feasibility of the approach was shown through imaging of an anthropomorphic phantom and the head-and-neck section of a lamb. TLD800 and EBT2 radiochromic film measurements were used to compare the VOI dose distributions with those for full-field techniques. CNR was measured for VOIs ranging from 4 to 15 cm diameter. The 2.35 MV/Carbon beam provides favorable CNR characteristics, although marked boundary and cupping artefacts arise due to truncation of projection data. These artefacts are largely eliminated using the DRR filling technique. Imaging dose was reduced by 5-10% and 75% inside and outside of the VOI, respectively, compared to full-field imaging for a cranial VOI. For the 2.35 MV/Carbon beam, CNR was shown to be approximately invariant with VOI dimension for bone and lung objects. This indicates that the advantage of the VOI approach with the low-Z target beam is substantial imaging dose reduction, not improvement of image quality. VOI CBCT using a 2.35 MV/Carbon beam is a feasible technique whereby a chosen imaging volume can be defined in the planning system and tracked during acquisition. The novel x-ray beam affords good CNR characteristics while imaging dose is localized to the chosen VOI. Funding for this project has been received from Varian Medical, Incorporated. © 2012 American Association of Physicists in Medicine.

  2. D-Cluster Converter Foil for Laser-Accelerated Deuteron Beams: Towards Deuteron-Beam-Driven Fast Ignition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miley, George H.

    Fast Ignition (FI) uses Petawatt laser generated particle beam pulse to ignite a small volume called a pre-compressed Inertial Confinement Fusion (ICF) target, and is the favored method to achieve the high energy gain per target burn needed for an attractive ICF power plant. Ion beams such as protons, deuterons or heavier carbon ions are especially appealing for FI as they have relative straight trajectory, and easier to focus on the fuel capsule. But current experiments have encountered problems with the 'converter-foil' which is irradiated by the Petawatt laser to produce the ion beams. The problems include depletion of themore » available ions in the convertor foils, and poor energy efficiency (ion beam energy/ input laser energy). We proposed to develop a volumetrically-loaded ultra-high-density deuteron deuterium cluster material as the basis for converter-foil for deuteron beam generation. The deuterons will fuse with the ICF DT while they slow down, providing an extra 'bonus' energy gain in addition to heating the hot spot. Also, due to the volumetric loading, the foil will provide sufficient energetic deuteron beam flux for 'hot spot' ignition, while avoiding the depletion problem encountered by current proton-driven FI foils. After extensive comparative studies, in Phase I, high purity PdO/Pd/PdO foils were selected for the high packing fraction D-Cluster converter foils. An optimized loading process has been developed to increase the cluster packing fraction in this type of foil. As a result, the packing fraction has been increased from 0.1% to 10% - meeting the original Phase I goal and representing a significant progress towards the beam intensities needed for both FI and pulsed neutron applications. Fast Ignition provides a promising approach to achieve high energy gain target performance needed for commercial Inertial Confinement Fusion (ICF). This is now a realistic goal for near term in view of the anticipated ICF target burn at the National

  3. 3D ultrasound volume stitching using phase symmetry and harris corner detection for orthopaedic applications

    NASA Astrophysics Data System (ADS)

    Dalvi, Rupin; Hacihaliloglu, Ilker; Abugharbieh, Rafeef

    2010-03-01

    Stitching of volumes obtained from three dimensional (3D) ultrasound (US) scanners improves visualization of anatomy in many clinical applications. Fast but accurate volume registration remains the key challenge in this area.We propose a volume stitching method based on efficient registration of 3D US volumes obtained from a tracked US probe. Since the volumes, after adjusting for probe motion, are coarsely registered, we obtain salient correspondence points in the central slices of these volumes. This is done by first removing artifacts in the US slices using intensity invariant local phase image processing and then applying the Harris Corner detection algorithm. Fast sub-volume registration on a small neighborhood around the points then gives fast, accurate 3D registration parameters. The method has been tested on 3D US scans of phantom and real human radius and pelvis bones and a phantom human fetus. The method has also been compared to volumetric registration, as well as feature based registration using 3D-SIFT. Quantitative results show average post-registration error of 0.33mm which is comparable to volumetric registration accuracy (0.31mm) and much better than 3D-SIFT based registration which failed to register the volumes. The proposed method was also much faster than volumetric registration (~4.5 seconds versus 83 seconds).

  4. Novel Fast Adapting Interneurons Mediate Cholinergic-Induced Fast GABAA IPSCs In Striatal Spiny Neurons

    PubMed Central

    Faust, Thomas W.; Assous, Maxime; Shah, Fulva; Tepper, James M.; Koós, Tibor

    2015-01-01

    Previous work suggests that neostriatal cholinergic interneurons control the activity of several classes of GABAergic interneurons through fast nicotinic receptor mediated synaptic inputs. Although indirect evidence has suggested the existence of several classes of interneurons controlled by this mechanism only one such cell type, the neuropeptide-Y expressing neurogliaform neuron, has been identified to date. Here we tested the hypothesis that in addition to the neurogliaform neurons that elicit slow GABAergic inhibitory responses, another interneuron type exists in the striatum that receives strong nicotinic cholinergic input and elicits conventional fast GABAergic synaptic responses in projection neurons. We obtained in vitro slice recordings from double transgenic mice in which Channelrhodopsin-2 was natively expressed in cholinergic neurons and a population of serotonin receptor-3a-Cre expressing GABAergic interneurons were visualized with tdTomato. We show that among the targeted GABAergic interneurons a novel type of interneuron, termed the fast-adapting interneuron, can be identified that is distinct from previously known interneurons based on immunocytochemical and electrophysiological criteria. We show using optogenetic activation of cholinergic inputs that fast-adapting interneurons receive a powerful supra-threshold nicotinic cholinergic input in vitro. Moreover, fast adapting neurons are densely connected to projection neurons and elicit fast, GABAA receptor mediated inhibitory postsynaptic responses. The nicotinic receptor mediated activation of fast-adapting interneurons may constitute an important mechanism through which cholinergic interneurons control the activity of projection neurons and perhaps the plasticity of their synaptic inputs when animals encounter reinforcing or otherwise salient stimuli. PMID:25865337

  5. Evaluation of dose coverage to target volume and normal tissue sparing in the adjuvant radiotherapy of gastric cancers: 3D-CRT compared with dynamic IMRT.

    PubMed

    Murthy, Kk; Shukeili, Ka; Kumar, Ss; Davis, Ca; Chandran, Rr; Namrata, S

    2010-01-01

    To assess the potential advantage of intensity-modulated radiotherapy (IMRT) over 3D-conformal radiotherapy (3D-CRT) planning in postoperative adjuvant radiotherapy for patients with gastric carcinoma. In a retrospective study, for plan comparison, dose distribution was recalculated in 15 patients treated with 3D-CRT on the contoured structures of same CT images using an IMRT technique. 3D-conformal plans with three fields and four-fields were compared with seven-field dynamic IMRT plans. The different plans were compared by analyzing the dose coverage of planning target volume using TV(95), D(mean), uniformity index, conformity index and homogeneity index parameters. To assess critical organ sparing, D(mean), D(max), dose to one-third and two-third volumes of the OARs and percentage of volumes receiving more than their tolerance doses were compared. The average dose coverage values of PTV with 3F-CRT and 4F-CRT plans were comparable, where as IMRT plans achieved better target coverage(p<0.001) with higher conformity index value of 0.81±0.07 compared to both the 3D-CRT plans. The doses to the liver and bowel reduced significantly (p<0.001) with IMRT plans compared to other 3D-CRT plans. For all OARs the percentage of volumes receiving more than their tolerance doses were reduced with the IMRT plans. This study showed that a better target coverage and significant dose reduction to OARs could be achieved with the IMRT plans. The IMRT can be preferred with caution for organ motion. The authors are currently studying organ motion in the upper abdomen to use IMRT for patient treatment.

  6. Comparing masked target transform volume (MTTV) clutter metric to human observer evaluation of visual clutter

    NASA Astrophysics Data System (ADS)

    Camp, H. A.; Moyer, Steven; Moore, Richard K.

    2010-04-01

    The Night Vision and Electronic Sensors Directorate's current time-limited search (TLS) model, which makes use of the targeting task performance (TTP) metric to describe image quality, does not explicitly account for the effects of visual clutter on observer performance. The TLS model is currently based on empirical fits to describe human performance for a time of day, spectrum and environment. Incorporating a clutter metric into the TLS model may reduce the number of these empirical fits needed. The masked target transform volume (MTTV) clutter metric has been previously presented and compared to other clutter metrics. Using real infrared imagery of rural images with varying levels of clutter, NVESD is currently evaluating the appropriateness of the MTTV metric. NVESD had twenty subject matter experts (SME) rank the amount of clutter in each scene in a series of pair-wise comparisons. MTTV metric values were calculated and then compared to the SME observers rankings. The MTTV metric ranked the clutter in a similar manner to the SME evaluation, suggesting that the MTTV metric may emulate SME response. This paper is a first step in quantifying clutter and measuring the agreement to subjective human evaluation.

  7. Impact of 4D-(18)FDG-PET/CT imaging on target volume delineation in SBRT patients with central versus peripheral lung tumors. Multi-reader comparative study.

    PubMed

    Chirindel, Alin; Adebahr, Sonja; Schuster, Daniel; Schimek-Jasch, Tanja; Schanne, Daniel H; Nemer, Ursula; Mix, Michael; Meyer, Philipp; Grosu, Anca-Ligia; Brunner, Thomas; Nestle, Ursula

    2015-06-01

    Evaluation of the effect of co-registered 4D-(18)FDG-PET/CT for SBRT target delineation in patients with central versus peripheral lung tumors. Analysis of internal target volume (ITV) delineation of central and peripheral lung lesions in 21 SBRT-patients. Manual delineation was performed by 4 observers in 2 contouring phases: on respiratory gated 4DCT with diagnostic 3DPET available aside (CT-ITV) and on co-registered 4DPET/CT (PET/CT-ITV). Comparative analysis of volumes and inter-reader agreement. 11 cases of peripheral and 10 central lesions were evaluated. In peripheral lesions, average CT-ITV was 6.2 cm(3) and PET/CT-ITV 8.6 cm(3), resembling a mean change in hypothetical radius of 2 mm. For both CT-ITVs and PET/CT-ITVs inter reader agreement was good and unchanged (0.733 and 0.716; p=0.58). All PET/CT-ITVs stayed within the PTVs derived from CT-ITVs. In central lesions, average CT-ITVs were 42.1 cm(3), PET/CT-ITVs 44.2 cm(3), without significant overall volume changes. Inter-reader agreement improved significantly (0.665 and 0.750; p<0.05). 2/10 PET/CT-ITVs exceeded the PTVs derived from CT-ITVs by >1 ml in average for all observers. The addition of co-registered 4DPET data to 4DCT based target volume delineation for SBRT of centrally located lung tumors increases the inter-observer agreement and may help to avoid geographic misses. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. The effect of Ramadan fasting on spatial attention through emotional stimuli

    PubMed Central

    Molavi, Maziyar; Yunus, Jasmy; Utama, Nugraha P

    2016-01-01

    Fasting can influence psychological and mental states. In the current study, the effect of periodical fasting on the process of emotion through gazed facial expression as a realistic multisource of social information was investigated for the first time. The dynamic cue-target task was applied via behavior and event-related potential measurements for 40 participants to reveal the temporal and spatial brain activities – before, during, and after fasting periods. The significance of fasting included several effects. The amplitude of the N1 component decreased over the centroparietal scalp during fasting. Furthermore, the reaction time during the fasting period decreased. The self-measurement of deficit arousal as well as the mood increased during the fasting period. There was a significant contralateral alteration of P1 over occipital area for the happy facial expression stimuli. The significant effect of gazed expression and its interaction with the emotional stimuli was indicated by the amplitude of N1. Furthermore, the findings of the study approved the validity effect as a congruency between gaze and target position, as indicated by the increment of P3 amplitude over centroparietal area as well as slower reaction time from behavioral response data during incongruency or invalid condition between gaze and target position compared with those during valid condition. Results of this study proved that attention to facial expression stimuli as a kind of communicative social signal was affected by fasting. Also, fasting improved the mood of practitioners. Moreover, findings from the behavioral and event-related potential data analyses indicated that the neural dynamics of facial emotion are processed faster than that of gazing, as the participants tended to react faster and prefer to relay on the type of facial emotions than to gaze direction while doing the task. Because of happy facial expression stimuli, right hemisphere activation was more than that of the left

  9. [Preoperative fasting period of fluids in bariatric surgery].

    PubMed

    Simon, P; Pietsch, U-C; Oesemann, R; Dietrich, A; Wrigge, H

    2017-07-01

    Aspiration of stomach content is a severe complication during general anaesthesia. The DGAI (German Society for Anesthesiology and Intensive Care Medicine) guidelines recommend a fasting period for liquids of 2 h, with a maximum of 400 ml. Preoperative fasting can affect the patients' recovery after surgery due to insulin resistance and higher protein catabolism as a response to surgical stress. The aim of the study was to compare a liberal fasting regimen consisting of up to 1000 ml of liquids until 2 h before surgery with the DGAI recommendation. The prospective observational clinical study was approved by the ethics committee of the University of Leipzig. In the liberal fasting group (G lib ) patients undergoing bariatric surgery were asked to drink 1000 ml of tea up to 2 h before surgery. Patients assigned to the restrictive fasting group (G res ) who were undergoing nonbariatric abdominal surgery were asked to drink no more than 400 ml of water up to 2 h preoperatively. Right after anaesthesia induction and intubation a gastric tube was placed, gastric residual volume was measured and the pH level of gastric fluid was determined. Moreover, the occurrence of aspiration was monitored. In all, 98 patients with a body mass index (BMI) of G lib 51.1 kg/m 2 and G res 26.5 kg/m 2 were identified. The preoperative fasting period of liquids was significantly different (G lib 170 min vs. G res 700 min, p < 0.001). There was no difference regarding the residual gastric volume (G lib 11 ml, G res 5 ml, p = 0.355). The pH of gastric fluid was nearly similar (G lib  4.0; G res  3.0; p = 0.864). Aspiration did not occur in any patient. There is evidence suggesting that a liberal fluid fasting regimen (1000 ml of fluid) in the preoperative period is safe in patients undergoing bariatric surgery.

  10. Fast Fourier Transform algorithm design and tradeoffs

    NASA Technical Reports Server (NTRS)

    Kamin, Ray A., III; Adams, George B., III

    1988-01-01

    The Fast Fourier Transform (FFT) is a mainstay of certain numerical techniques for solving fluid dynamics problems. The Connection Machine CM-2 is the target for an investigation into the design of multidimensional Single Instruction Stream/Multiple Data (SIMD) parallel FFT algorithms for high performance. Critical algorithm design issues are discussed, necessary machine performance measurements are identified and made, and the performance of the developed FFT programs are measured. Fast Fourier Transform programs are compared to the currently best Cray-2 FFT program.

  11. Utilization of PET-CT in target volume delineation for three-dimensional conformal radiotherapy in patients with non-small cell lung cancer and atelectasis.

    PubMed

    Yin, Li-Jie; Yu, Xiao-Bin; Ren, Yan-Gang; Gu, Guang-Hai; Ding, Tian-Gui; Lu, Zhi

    2013-03-18

    To investigate the utilization of PET-CT in target volume delineation for three-dimensional conformal radiotherapy in patients with non-small cell lung cancer (NSCLC) and atelectasis. Thirty NSCLC patients who underwent radical radiotherapy from August 2010 to March 2012 were included in this study. All patients were pathologically confirmed to have atelectasis by imaging examination. PET-CT scanning was performed in these patients. According to the PET-CT scan results, the gross tumor volume (GTV) and organs at risk (OARs, including the lungs, heart, esophagus and spinal cord) were delineated separately both on CT and PET-CT images. The clinical target volume (CTV) was defined as the GTV plus a margin of 6-8 mm, and the planning target volume (PTV) as the GTV plus a margin of 10-15mm. An experienced physician was responsible for designing treatment plans PlanCT and PlanPET-CT on CT image sets. 95% of the PTV was encompassed by the 90% isodose curve, and the two treatment plans kept the same beam direction, beam number, gantry angle, and position of the multi-leaf collimator as much as possible. The GTV was compared using a target delineation system, and doses distributions to OARs were compared on the basis of dose-volume histogram (DVH) parameters. The GTVCT and GTVPET-CT had varying degrees of change in all 30 patients, and the changes in the GTVCT and GTVPET-CT exceeded 25% in 12 (40%) patients. The GTVPET-CT decreased in varying degrees compared to the GTVCT in 22 patients. Their median GTVPET-CT and median GTVPET-CT were 111.4 cm3 (range, 37.8 cm3-188.7 cm3) and 155.1 cm3 (range, 76.2 cm3-301.0 cm3), respectively, and the former was 43.7 cm3 (28.2%) less than the latter. The GTVPET-CT increased in varying degrees compared to the GTVCT in 8 patients. Their median GTVPET-CT and median GTVPET-CT were 144.7 cm3 (range, 125.4 cm3-178.7 cm3) and 125.8 cm3 (range, 105.6 cm3-153.5 cm3), respectively, and the former was 18.9 cm3 (15.0%) greater than the latter

  12. A fast ellipse extended target PHD filter using box-particle implementation

    NASA Astrophysics Data System (ADS)

    Zhang, Yongquan; Ji, Hongbing; Hu, Qi

    2018-01-01

    This paper presents a box-particle implementation of the ellipse extended target probability hypothesis density (ET-PHD) filter, called the ellipse extended target box particle PHD (EET-BP-PHD) filter, where the extended targets are described as a Poisson model developed by Gilholm et al. and the term "box" is here equivalent to the term "interval" used in interval analysis. The proposed EET-BP-PHD filter is capable of dynamically tracking multiple ellipse extended targets and estimating the target states and the number of targets, in the presence of clutter measurements, false alarms and missed detections. To derive the PHD recursion of the EET-BP-PHD filter, a suitable measurement likelihood is defined for a given partitioning cell, and the main implementation steps are presented along with the necessary box approximations and manipulations. The limitations and capabilities of the proposed EET-BP-PHD filter are illustrated by simulation examples. The simulation results show that a box-particle implementation of the ET-PHD filter can avoid the high number of particles and reduce computational burden, compared to a particle implementation of that for extended target tracking.

  13. Factors influencing the measurement of closing volume.

    PubMed

    Make, B; Lapp, N L

    1975-06-01

    The various factors influencing closing volume were studied by performing the single-breath N2 test on 9 healthy nonsmokers. Time of day, day of the week, and preceding volume history had no effect on either closing volume or alveolar plateau. Slow inspiratory flow resulted in larger ratio of closing volume to vital capacity, ratio of closing capacity to total lung capacity, and change in N2 concentration than fast inspiratory flow. Voluntary regulation of the expiratory flow resulted in smaller ratios of closing volume to vital capacity and closing capacity to total lung capacity than when flow was regulated by a resistance. Prolonged breath holding of the inspired O2 led to larger ratio of closing volume to vital capacity and ratio of closing capacity to total lung capacity. To obtain uniform, comparable closing volumes, it is suggested that the subject inspire slowly, control expiratory flow (preferably voluntarily), and not pause between inspiration and expiration.

  14. Single-Isocenter Multiple-Target Stereotactic Radiosurgery: Risk of Compromised Coverage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roper, Justin, E-mail: justin.roper@emory.edu; Department of Biostatistics and Bioinformatics, Winship Cancer Institute of Emory University, Atlanta, Georgia; Chanyavanich, Vorakarn

    2015-11-01

    Purpose: To determine the dosimetric effects of rotational errors on target coverage using volumetric modulated arc therapy (VMAT) for multitarget stereotactic radiosurgery (SRS). Methods and Materials: This retrospective study included 50 SRS cases, each with 2 intracranial planning target volumes (PTVs). Both PTVs were planned for simultaneous treatment to 21 Gy using a single-isocenter, noncoplanar VMAT SRS technique. Rotational errors of 0.5°, 1.0°, and 2.0° were simulated about all axes. The dose to 95% of the PTV (D95) and the volume covered by 95% of the prescribed dose (V95) were evaluated using multivariate analysis to determine how PTV coverage was relatedmore » to PTV volume, PTV separation, and rotational error. Results: At 0.5° rotational error, D95 values and V95 coverage rates were ≥95% in all cases. For rotational errors of 1.0°, 7% of targets had D95 and V95 values <95%. Coverage worsened substantially when the rotational error increased to 2.0°: D95 and V95 values were >95% for only 63% of the targets. Multivariate analysis showed that PTV volume and distance to isocenter were strong predictors of target coverage. Conclusions: The effects of rotational errors on target coverage were studied across a broad range of SRS cases. In general, the risk of compromised coverage increased with decreasing target volume, increasing rotational error and increasing distance between targets. Multivariate regression models from this study may be used to quantify the dosimetric effects of rotational errors on target coverage given patient-specific input parameters of PTV volume and distance to isocenter.« less

  15. System and method for radiation dose calculation within sub-volumes of a monte carlo based particle transport grid

    DOEpatents

    Bergstrom, Paul M.; Daly, Thomas P.; Moses, Edward I.; Patterson, Jr., Ralph W.; Schach von Wittenau, Alexis E.; Garrett, Dewey N.; House, Ronald K.; Hartmann-Siantar, Christine L.; Cox, Lawrence J.; Fujino, Donald H.

    2000-01-01

    A system and method is disclosed for radiation dose calculation within sub-volumes of a particle transport grid. In a first step of the method voxel volumes enclosing a first portion of the target mass are received. A second step in the method defines dosel volumes which enclose a second portion of the target mass and overlap the first portion. A third step in the method calculates common volumes between the dosel volumes and the voxel volumes. A fourth step in the method identifies locations in the target mass of energy deposits. And, a fifth step in the method calculates radiation doses received by the target mass within the dosel volumes. A common volume calculation module inputs voxel volumes enclosing a first portion of the target mass, inputs voxel mass densities corresponding to a density of the target mass within each of the voxel volumes, defines dosel volumes which enclose a second portion of the target mass and overlap the first portion, and calculates common volumes between the dosel volumes and the voxel volumes. A dosel mass module, multiplies the common volumes by corresponding voxel mass densities to obtain incremental dosel masses, and adds the incremental dosel masses corresponding to the dosel volumes to obtain dosel masses. A radiation transport module identifies locations in the target mass of energy deposits. And, a dose calculation module, coupled to the common volume calculation module and the radiation transport module, for calculating radiation doses received by the target mass within the dosel volumes.

  16. SU-C-BRA-05: Delineating High-Dose Clinical Target Volumes for Head and Neck Tumors Using Machine Learning Algorithms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cardenas, C; The University of Texas Graduate School of Biomedical Sciences, Houston, TX; Wong, A

    Purpose: To develop and test population-based machine learning algorithms for delineating high-dose clinical target volumes (CTVs) in H&N tumors. Automating and standardizing the contouring of CTVs can reduce both physician contouring time and inter-physician variability, which is one of the largest sources of uncertainty in H&N radiotherapy. Methods: Twenty-five node-negative patients treated with definitive radiotherapy were selected (6 right base of tongue, 11 left and 9 right tonsil). All patients had GTV and CTVs manually contoured by an experienced radiation oncologist prior to treatment. This contouring process, which is driven by anatomical, pathological, and patient specific information, typically results inmore » non-uniform margin expansions about the GTV. Therefore, we tested two methods to delineate high-dose CTV given a manually-contoured GTV: (1) regression-support vector machines(SVM) and (2) classification-SVM. These models were trained and tested on each patient group using leave-one-out cross-validation. The volume difference(VD) and Dice similarity coefficient(DSC) between the manual and auto-contoured CTV were calculated to evaluate the results. Distances from GTV-to-CTV were computed about each patient’s GTV and these distances, in addition to distances from GTV to surrounding anatomy in the expansion direction, were utilized in the regression-SVM method. The classification-SVM method used categorical voxel-information (GTV, selected anatomical structures, else) from a 3×3×3cm3 ROI centered about the voxel to classify voxels as CTV. Results: Volumes for the auto-contoured CTVs ranged from 17.1 to 149.1cc and 17.4 to 151.9cc; the average(range) VD between manual and auto-contoured CTV were 0.93 (0.48–1.59) and 1.16(0.48–1.97); while average(range) DSC values were 0.75(0.59–0.88) and 0.74(0.59–0.81) for the regression-SVM and classification-SVM methods, respectively. Conclusion: We developed two novel machine learning methods to

  17. Fast super-resolution estimation of DOA and DOD in bistatic MIMO Radar with off-grid targets

    NASA Astrophysics Data System (ADS)

    Zhang, Dong; Zhang, Yongshun; Zheng, Guimei; Feng, Cunqian; Tang, Jun

    2018-05-01

    In this paper, we focus on the problem of joint DOA and DOD estimation in Bistatic MIMO Radar using sparse reconstruction method. In traditional ways, we usually convert the 2D parameter estimation problem into 1D parameter estimation problem by Kronecker product which will enlarge the scale of the parameter estimation problem and bring more computational burden. Furthermore, it requires that the targets must fall on the predefined grids. In this paper, a 2D-off-grid model is built which can solve the grid mismatch problem of 2D parameters estimation. Then in order to solve the joint 2D sparse reconstruction problem directly and efficiently, three kinds of fast joint sparse matrix reconstruction methods are proposed which are Joint-2D-OMP algorithm, Joint-2D-SL0 algorithm and Joint-2D-SOONE algorithm. Simulation results demonstrate that our methods not only can improve the 2D parameter estimation accuracy but also reduce the computational complexity compared with the traditional Kronecker Compressed Sensing method.

  18. Magnetic Resonance Venous Volume Measurements in Peripheral Artery Disease (from ELIMIT).

    PubMed

    Kamran, Hassan; Nambi, Vijay; Negi, Smita; Yang, Eric Y; Chen, Changyi; Virani, Salim S; Kougias, Panos; Lumsden, Alan B; Morrisett, Joel D; Ballantyne, Christie M; Brunner, Gerd

    2016-11-01

    The relation between the arterial and venous systems in patients with impaired lower extremity blood flow remains poorly described. The objective of this secondary analysis of the Effectiveness of Intensive Lipid Modification Medication in Preventing the Progression on Peripheral Artery Disease Trial was to determine the association between femoral vein (FV) volumes and measurements of peripheral artery disease. FV wall, lumen, and total volumes were quantified with fast spin-echo proton density-weighted magnetic resonance imaging scans in 79 patients with peripheral artery disease over 2 years. Reproducibility was excellent for FV total vessel (intraclass correlation coefficient 0.924, confidence interval 0.910 to 0.935) and lumen volumes (intraclass correlation coefficient 0.893, confidence interval 0.873 to 0.910). Baseline superficial femoral artery volumes were directly associated with FV wall (r = 0.46, p <0.0001), lumen (r = 0.42, p = 0.0001), and total volumes (r = 0.46, p <0.0001). The 2-year change in maximum walking time was inversely associated with the 24-month change in FV total volume (r = -0.45, p = 0.03). In conclusion, FV volumes can be measured reliably with fast spin-echo proton density-weighted magnetic resonance imaging, and baseline superficial femoral artery plaque burden is positively associated with FV volumes, whereas the 2-year change in FV volumes and leg function show an inverse relation. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Fast iterative censoring CFAR algorithm for ship detection from SAR images

    NASA Astrophysics Data System (ADS)

    Gu, Dandan; Yue, Hui; Zhang, Yuan; Gao, Pengcheng

    2017-11-01

    Ship detection is one of the essential techniques for ship recognition from synthetic aperture radar (SAR) images. This paper presents a fast iterative detection procedure to eliminate the influence of target returns on the estimation of local sea clutter distributions for constant false alarm rate (CFAR) detectors. A fast block detector is first employed to extract potential target sub-images; and then, an iterative censoring CFAR algorithm is used to detect ship candidates from each target blocks adaptively and efficiently, where parallel detection is available, and statistical parameters of G0 distribution fitting local sea clutter well can be quickly estimated based on an integral image operator. Experimental results of TerraSAR-X images demonstrate the effectiveness of the proposed technique.

  20. Validation approach for a fast and simple targeted screening method for 75 antibiotics in meat and aquaculture products using LC-MS/MS.

    PubMed

    Dubreil, Estelle; Gautier, Sophie; Fourmond, Marie-Pierre; Bessiral, Mélaine; Gaugain, Murielle; Verdon, Eric; Pessel, Dominique

    2017-04-01

    An approach is described to validate a fast and simple targeted screening method for antibiotic analysis in meat and aquaculture products by LC-MS/MS. The strategy of validation was applied for a panel of 75 antibiotics belonging to different families, i.e., penicillins, cephalosporins, sulfonamides, macrolides, quinolones and phenicols. The samples were extracted once with acetonitrile, concentrated by evaporation and injected into the LC-MS/MS system. The approach chosen for the validation was based on the Community Reference Laboratory (CRL) guidelines for the validation of screening qualitative methods. The aim of the validation was to prove sufficient sensitivity of the method to detect all the targeted antibiotics at the level of interest, generally the maximum residue limit (MRL). A robustness study was also performed to test the influence of different factors. The validation showed that the method is valid to detect and identify 73 antibiotics of the 75 antibiotics studied in meat and aquaculture products at the validation levels.

  1. TAPIR, a web server for the prediction of plant microRNA targets, including target mimics.

    PubMed

    Bonnet, Eric; He, Ying; Billiau, Kenny; Van de Peer, Yves

    2010-06-15

    We present a new web server called TAPIR, designed for the prediction of plant microRNA targets. The server offers the possibility to search for plant miRNA targets using a fast and a precise algorithm. The precise option is much slower but guarantees to find less perfectly paired miRNA-target duplexes. Furthermore, the precise option allows the prediction of target mimics, which are characterized by a miRNA-target duplex having a large loop, making them undetectable by traditional tools. The TAPIR web server can be accessed at: http://bioinformatics.psb.ugent.be/webtools/tapir. Supplementary data are available at Bioinformatics online.

  2. High-current fast electron beam propagation in a dielectric target.

    PubMed

    Klimo, Ondrej; Tikhonchuk, V T; Debayle, A

    2007-01-01

    Recent experiments demonstrate an efficient transformation of high intensity laser pulse into a relativistic electron beam with a very high current density exceeding 10(12) A cm(-2). The propagation of such a beam inside the target is possible if its current is neutralized. This phenomenon is not well understood, especially in dielectric targets. In this paper, we study the propagation of high current density electron beam in a plastic target using a particle-in-cell simulation code. The code includes both ionization of the plastic and collisions of newborn electrons. The numerical results are compared with a relatively simple analytical model and a reasonable agreement is found. The temporal evolution of the beam velocity distribution, the spatial density profile, and the propagation velocity of the ionization front are analyzed and their dependencies on the beam density and energy are discussed. The beam energy losses are mainly due to the target ionization induced by the self-generated electric field and the return current. For the highest beam density, a two-stream instability is observed to develop in the plasma behind the ionization front and it contributes to the beam energy losses.

  3. Fast-food intake and perceived and objective measures of the local fast-food environment in adolescents.

    PubMed

    Svastisalee, Chalida; Pagh Pedersen, Trine; Schipperijn, Jasper; Jørgensen, Sanne Ellegaard; Holstein, Bjørn E; Krølner, Rikke

    2016-02-01

    We examined associations between fast-food intake and perceived and objective fast-food outlet exposure. Information from the Health Behaviours in School-aged Children Study was linked to fast-food outlets in seventy-five school neighbourhoods. We used multivariate multilevel logistic regression analyses to examine associations between at least weekly fast-food intake and perceived and objective fast-food outlet measures. Data represent 4642 adolescents (aged 11-15 years) in Denmark. Boys reporting two or more fast-food outlets had 34% higher odds consuming fast food at least weekly. We detected higher odds of at least weekly fast-food intake among 15-year-old 9th graders (ORall=1.74; 95% CI 1.40, 2.18; ORboys=2.20; 95% CI 1.66, 2.91; ORgirls=1.41; 95% CI 1.03, 1.92), Danish speakers (ORall=2.32; 95% CI 1.68, 3.19; ORboys=2.58; 95% CI 1.69, 3.93; ORgirls=2.37; 95% CI 1.46, 3.84) and those travelling 15 min or less to school (ORall=1.21; 95% CI 1.00, 1.46; ORgirls=1.44; 95% CI 1.08, 1.93) compared with 11-year-old 5th graders, non-Danish speakers and those with longer travel times. Boys from middle- (OR=1.28; 95% CI 1.00, 1.65) and girls from low-income families (OR=1.46; 95% CI 1.05, 2.04) had higher odds of at least weekly fast-food intake compared with those from high-income backgrounds. Girls attending schools with canteens (OR=1.47; 95% CI 1.00, 2.15) had higher odds of at least weekly fast-food intake than girls at schools without canteens. The present study demonstrates that perceived food outlets may impact fast-food intake in boys while proximity impacts intake in girls. Public health planning could target food environments that emphasize a better understanding of how adolescents use local resources.

  4. Absolute and relative densities of fast-food versus other restaurants in relation to weight status: Does restaurant mix matter?

    PubMed

    Polsky, Jane Y; Moineddin, Rahim; Dunn, James R; Glazier, Richard H; Booth, Gillian L

    2016-01-01

    Given the continuing epidemic of obesity, policymakers are increasingly looking for levers within the local retail food environment as a means of promoting healthy weights. To examine the independent and joint associations of absolute and relative densities of restaurants near home with weight status in a large, urban, population-based sample of adults. We studied 10,199 adults living in one of four cities in southern Ontario, Canada, who participated in the Canadian Community Health Survey (cycles 2005, 2007/08, 2009/10). Multivariate models assessed the association of weight status (obesity and body mass index) with absolute densities (numbers) of fast-food, full-service and other restaurants, and the relative density (proportion) of fast-food restaurants (FFR) relative to all restaurants within ~10-minute walk of residential areas. Higher numbers of restaurants of any type were inversely related to excess weight, even in models adjusting for a range of individual covariates and area deprivation. However, these associations were no longer significant after accounting for higher walkability of areas with high volumes of restaurants. In contrast, there was a direct relationship between the proportion of FFR relative to all restaurants and excess weight, particularly in areas with high volumes of FFR (e.g., odds ratio for obesity=2.55 in areas with 5+ FFR, 95% confidence interval: 1.55-4.17, across the interquartile range). Policies aiming to promote healthy weights that target the volume of certain retail food outlets in residential settings may be more effective if they also consider the relative share of outlets serving more and less healthful foods. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Free Volume Structure of Acrylic-Type Dental Nanocomposites Tested with Annihilating Positrons.

    PubMed

    Shpotyuk, Olha; Ingram, Adam; Shpotyuk, Oleh

    2016-12-01

    Positron annihilation spectroscopy in lifetime measuring mode exploring conventional fast-fast coincidence ORTEC system is employed to characterize free volume structure of commercially available acrylic-type dental restorative composite Charisma® (Heraeus Kulzer GmbH, Germany). The measured lifetime spectra for uncured and light-cured composites are reconstructed from unconstrained x3-term fitting and semi-empirical model exploring x3-x2-coupling decomposition algorithm. The governing channel of positron annihilation in the composites studied is ascribed to mixed positron-Ps trapping, where Ps decaying in the third component is caused entirely by input from free-volume holes in polymer matrix, while the second component is defined by free positron trapping in interfacial free-volume holes between filler nanoparticles and surrounded polymer matrix. Microstructure scenario of the photopolymerization shrinkage includes cross-linking of structural chains in polymer matrix followed by conversion of bound positron-electron (positronium) traps in positron-trapping interfacial free-volume voids in a vicinity of agglomerated filler nanoparticles.

  6. Noninvasive, low-noise, fast imaging of blood volume and deoxygenation changes in muscles using light-emitting diode continuous-wave imager

    NASA Astrophysics Data System (ADS)

    Lin, Yuanqing; Lech, Gwen; Nioka, Shoko; Intes, Xavier; Chance, Britton

    2002-08-01

    This article focuses on optimizing the signal to noise ratio (SNR) of a three-wavelength light-emitting diode (LED) near-infrared continuous-wave (cw) imager and its application to in vivo muscle metabolism measurement. The shot-noise limited SNR is derived and calculated to be 2 x104 for the physiological blood concentrations of muscle. Aiming at shot-noise limited SNR performance and fast imaging, we utilize sample and hold circuits to reduce high-frequency noise. These circuits have also been designed to be parallel integrating, through which SNR of 2 x103 and 2 Hz imaging acquisition rate have been achieved when the probe is placed on a muscle model. The noise corresponds to 2 x10-4 optical density error, which suggests an in vitro resolution of 15. 4 nM blood volume and 46.8 nM deoxygenation changes. A 48 dB digital gain control circuit with 256 steps is employed to enlarge the dynamic range of the imager. We utilize cuff ischemia as a living model demonstration and its results are reported. The instrument is applied during exercise to measure the changes of blood volume and deoxygenation, which provides important information about muscle metabolism. We find that the primary source of noise encountered during exercise experiment is from the random motion of muscle. The results demonstrate that the LED cw imager is ideal for the noninvasive study of muscle metabolism.

  7. Real-time Interpolation for True 3-Dimensional Ultrasound Image Volumes

    PubMed Central

    Ji, Songbai; Roberts, David W.; Hartov, Alex; Paulsen, Keith D.

    2013-01-01

    We compared trilinear interpolation to voxel nearest neighbor and distance-weighted algorithms for fast and accurate processing of true 3-dimensional ultrasound (3DUS) image volumes. In this study, the computational efficiency and interpolation accuracy of the 3 methods were compared on the basis of a simulated 3DUS image volume, 34 clinical 3DUS image volumes from 5 patients, and 2 experimental phantom image volumes. We show that trilinear interpolation improves interpolation accuracy over both the voxel nearest neighbor and distance-weighted algorithms yet achieves real-time computational performance that is comparable to the voxel nearest neighbor algrorithm (1–2 orders of magnitude faster than the distance-weighted algorithm) as well as the fastest pixel-based algorithms for processing tracked 2-dimensional ultrasound images (0.035 seconds per 2-dimesional cross-sectional image [76,800 pixels interpolated, or 0.46 ms/1000 pixels] and 1.05 seconds per full volume with a 1-mm3 voxel size [4.6 million voxels interpolated, or 0.23 ms/1000 voxels]). On the basis of these results, trilinear interpolation is recommended as a fast and accurate interpolation method for rectilinear sampling of 3DUS image acquisitions, which is required to facilitate subsequent processing and display during operating room procedures such as image-guided neurosurgery. PMID:21266563

  8. Real-time interpolation for true 3-dimensional ultrasound image volumes.

    PubMed

    Ji, Songbai; Roberts, David W; Hartov, Alex; Paulsen, Keith D

    2011-02-01

    We compared trilinear interpolation to voxel nearest neighbor and distance-weighted algorithms for fast and accurate processing of true 3-dimensional ultrasound (3DUS) image volumes. In this study, the computational efficiency and interpolation accuracy of the 3 methods were compared on the basis of a simulated 3DUS image volume, 34 clinical 3DUS image volumes from 5 patients, and 2 experimental phantom image volumes. We show that trilinear interpolation improves interpolation accuracy over both the voxel nearest neighbor and distance-weighted algorithms yet achieves real-time computational performance that is comparable to the voxel nearest neighbor algrorithm (1-2 orders of magnitude faster than the distance-weighted algorithm) as well as the fastest pixel-based algorithms for processing tracked 2-dimensional ultrasound images (0.035 seconds per 2-dimesional cross-sectional image [76,800 pixels interpolated, or 0.46 ms/1000 pixels] and 1.05 seconds per full volume with a 1-mm(3) voxel size [4.6 million voxels interpolated, or 0.23 ms/1000 voxels]). On the basis of these results, trilinear interpolation is recommended as a fast and accurate interpolation method for rectilinear sampling of 3DUS image acquisitions, which is required to facilitate subsequent processing and display during operating room procedures such as image-guided neurosurgery.

  9. Fast and cost-effective cyclotron production of 61Cu using a natZn liquid target: an opportunity for radiopharmaceutical production and R&D.

    PubMed

    do Carmo, S J C; Alves, V H P; Alves, F; Abrunhosa, A J

    2017-10-31

    Following our previous work on the production of radiometals, such as 64 Cu and 68 Ga, through the irradiation of liquid targets using a medical cyclotron, we describe in this paper a technique to produce 61 Cu through the irradiation of natural zinc using a liquid target. The proposed method is very cost-effective, as it avoids the use of expensive enriched material, and is fast, as a purified solution of 61 CuCl 2 is obtained in less than 30 min after the end of beam. Considering its moderate half-life of 3.33 h and favourable decay properties as a positron emitter, 61 Cu is a very attractive nuclide for the labelling of PET tracers for pre-clinical and clinical use with PET as well as to support the intense R&D programmes being carried out worldwide by taking advantage of the rich and versatile chemistry of copper.

  10. EFFECTS OF LASER RADIATION ON MATTER. LASER PLASMA: Conversion of the energy of fast electrons to thermal plasma radiation

    NASA Astrophysics Data System (ADS)

    Vergunova, G. A.; Rozanov, Vladislav B.

    1992-01-01

    An analysis is made of the conversion of the energy of highly energetic fast electrons, generated by the action of CO2 laser radiation on a target, into characteristic radiation emitted by a plasma formed from shell targets which, for instance, may be present inside targets irradiated by the CO2 laser. Analytical formulas are obtained for the temperature of the converted radiation. The results show that it is possible to control this radiation by choosing the parameters of the target and of the fast electron flux. The efficiency of conversion into characteristic thermal radiation is found numerically to be 95%. This method of conversion is more favorable than direct interaction of CO2 laser radiation with a target since the emitting region is localized in the target mass. When a laser interacts with a target the mass of this region increases with time and so the temperature of the emitted radiation is lower than in the case when fast electrons act on the target.

  11. Ivy and neurogliaform interneurons are a major target of μ opioid receptor modulation

    PubMed Central

    Krook-Magnuson, Esther; Luu, Lillian; Lee, Sang-Hun; Varga, Csaba; Soltesz, Ivan

    2011-01-01

    Mu opioid receptors (μORs) are selectively expressed on interneurons in area CA1 of the hippocampus. Fast-spiking, parvalbumin expressing, basket cells express μORs, but circumstantial evidence suggests that another major, unidentified, GABAergic cell class must also be modulated by μORs. Here we report that the abundant, dendritically targeting, neurogliaform family of cells (Ivy and neurogliaform cells) is a previously unrecognized target of direct modulation by μORs. Ivy and neurogliaform cells are not only numerous, but also have unique properties, including promiscuous gap junctions formed with various interneuronal subtypes, volume transmission, and the ability to produce a postsynaptic GABAB response after a single presynaptic spike. Using a mouse line expressing green fluorescent protein under the neuropeptide Y promoter, we find that across all layers of CA1, activation of μORs hyperpolarizes Ivy and neurogliaform cells. Further, paired recordings between synaptically coupled Ivy and pyramidal cells show that Ivy cell terminals are dramatically inhibited by μOR-activation. Effects in Ivy and neurogliaform cells are seen at similar concentrations of agonist as those producing inhibition in fast-spiking PV basket cells. We also report that Ivy cells display the recently described phenomenon of persistent firing, a state of continued firing in the absence of continued input, and that induction of persistent firing is inhibited by μOR-activation. Together these findings identify a major, previously unrecognized, target of μOR-modulation. Given the prominence of this cell type in and beyond CA1, as well as its unique role in microcircuitry, opioid modulation of neurogliaform cells has wide implications. PMID:22016519

  12. Ivy and neurogliaform interneurons are a major target of μ-opioid receptor modulation.

    PubMed

    Krook-Magnuson, Esther; Luu, Lillian; Lee, Sang-Hun; Varga, Csaba; Soltesz, Ivan

    2011-10-19

    μ-Opioid receptors (μORs) are selectively expressed on interneurons in area CA1 of the hippocampus. Fast-spiking, parvalbumin-expressing, basket cells express μORs, but circumstantial evidence suggests that another major, unidentified, GABAergic cell class must also be modulated by μORs. Here we report that the abundant, dendritically targeting, neurogliaform family of cells (Ivy and neurogliaform cells) is a previously unrecognized target of direct modulation by μORs. Ivy and neurogliaform cells are not only numerous but also have unique properties, including promiscuous gap junctions formed with various interneuronal subtypes, volume transmission, and the ability to produce a postsynaptic GABA(B) response after a single presynaptic spike. Using a mouse line expressing green fluorescent protein under the neuropeptide Y promoter, we find that, across all layers of CA1, activation of μORs hyperpolarizes Ivy and neurogliaform cells. Furthermore, paired recordings between synaptically coupled Ivy and pyramidal cells show that Ivy cell terminals are dramatically inhibited by μOR activation. Effects in Ivy and neurogliaform cells are seen at similar concentrations of agonist as those producing inhibition in fast-spiking parvalbumin basket cells. We also report that Ivy cells display the recently described phenomenon of persistent firing, a state of continued firing in the absence of continued input, and that induction of persistent firing is inhibited by μOR activation. Together, these findings identify a major, previously unrecognized, target of μOR modulation. Given the prominence of this cell type in and beyond CA1, as well as its unique role in microcircuitry, opioid modulation of neurogliaform cells has wide implications.

  13. Fast and Adaptive Lossless On-Board Hyperspectral Data Compression System for Space Applications

    NASA Technical Reports Server (NTRS)

    Aranki, Nazeeh; Bakhshi, Alireza; Keymeulen, Didier; Klimesh, Matthew

    2009-01-01

    Efficient on-board lossless hyperspectral data compression reduces the data volume necessary to meet NASA and DoD limited downlink capabilities. The techniques also improves signature extraction, object recognition and feature classification capabilities by providing exact reconstructed data on constrained downlink resources. At JPL a novel, adaptive and predictive technique for lossless compression of hyperspectral data was recently developed. This technique uses an adaptive filtering method and achieves a combination of low complexity and compression effectiveness that far exceeds state-of-the-art techniques currently in use. The JPL-developed 'Fast Lossless' algorithm requires no training data or other specific information about the nature of the spectral bands for a fixed instrument dynamic range. It is of low computational complexity and thus well-suited for implementation in hardware, which makes it practical for flight implementations of pushbroom instruments. A prototype of the compressor (and decompressor) of the algorithm is available in software, but this implementation may not meet speed and real-time requirements of some space applications. Hardware acceleration provides performance improvements of 10x-100x vs. the software implementation (about 1M samples/sec on a Pentium IV machine). This paper describes a hardware implementation of the JPL-developed 'Fast Lossless' compression algorithm on a Field Programmable Gate Array (FPGA). The FPGA implementation targets the current state of the art FPGAs (Xilinx Virtex IV and V families) and compresses one sample every clock cycle to provide a fast and practical real-time solution for Space applications.

  14. Variation in the Gross Tumor Volume and Clinical Target Volume for Preoperative Radiotherapy of Primary Large High-Grade Soft Tissue Sarcoma of the Extremity Among RTOG Sarcoma Radiation Oncologists

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang Dian, E-mail: dwang@mcw.edu; Bosch, Walter; Kirsch, David G.

    Purpose: To evaluate variability in the definition of preoperative radiotherapy gross tumor volume (GTV) and clinical target volume (CTV) delineated by sarcoma radiation oncologists. Methods and Materials: Extremity sarcoma planning CT images along with the corresponding diagnostic MRI from two patients were distributed to 10 Radiation Therapy Oncology Group sarcoma radiation oncologists with instructions to define GTV and CTV using standardized guidelines. The CT data with contours were then returned for central analysis. Contours representing statistically corrected 95% (V95) and 100% (V100) agreement were computed for each structure. Results: For the GTV, the minimum, maximum, mean (SD) volumes (mL) weremore » 674, 798, 752 {+-} 35 for the lower extremity case and 383, 543, 447 {+-} 46 for the upper extremity case. The volume (cc) of the union, V95 and V100 were 882, 761, and 752 for the lower, and 587, 461, and 455 for the upper extremity, respectively. The overall GTV agreement was judged to be almost perfect in both lower and upper extremity cases (kappa = 0.9 [p < 0.0001] and kappa = 0.86 [p < 0.0001]). For the CTV, the minimum, maximum, mean (SD) volumes (mL) were 1145, 1911, 1605 {+-} 211 for the lower extremity case and 637, 1246, 1006 {+-} 180 for the upper extremity case. The volume (cc) of the union, V95, and V100 were 2094, 1609, and 1593 for the lower, and 1533, 1020, and 965 for the upper extremity cases, respectively. The overall CTV agreement was judged to be almost perfect in the lower extremity case (kappa = 0.85 [p < 0.0001]) but only substantial in the upper extremity case (kappa = 0.77 [p < 0.0001]). Conclusions: Almost perfect agreement existed in the GTV of these two representative cases. Tshere was no significant disagreement in the CTV of the lower extremity, but variation in the CTV of upper extremity was seen, perhaps related to the positional differences between the planning CT and the diagnostic MRI.« less

  15. SU-F-BRD-07: Fast Monte Carlo-Based Biological Optimization of Proton Therapy Treatment Plans for Thyroid Tumors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wan Chan Tseung, H; Ma, J; Ma, D

    2015-06-15

    Purpose: To demonstrate the feasibility of fast Monte Carlo (MC) based biological planning for the treatment of thyroid tumors in spot-scanning proton therapy. Methods: Recently, we developed a fast and accurate GPU-based MC simulation of proton transport that was benchmarked against Geant4.9.6 and used as the dose calculation engine in a clinically-applicable GPU-accelerated IMPT optimizer. Besides dose, it can simultaneously score the dose-averaged LET (LETd), which makes fast biological dose (BD) estimates possible. To convert from LETd to BD, we used a linear relation based on cellular irradiation data. Given a thyroid patient with a 93cc tumor volume, we createdmore » a 2-field IMPT plan in Eclipse (Varian Medical Systems). This plan was re-calculated with our MC to obtain the BD distribution. A second 5-field plan was made with our in-house optimizer, using pre-generated MC dose and LETd maps. Constraints were placed to maintain the target dose to within 25% of the prescription, while maximizing the BD. The plan optimization and calculation of dose and LETd maps were performed on a GPU cluster. The conventional IMPT and biologically-optimized plans were compared. Results: The mean target physical and biological doses from our biologically-optimized plan were, respectively, 5% and 14% higher than those from the MC re-calculation of the IMPT plan. Dose sparing to critical structures in our plan was also improved. The biological optimization, including the initial dose and LETd map calculations, can be completed in a clinically viable time (∼30 minutes) on a cluster of 25 GPUs. Conclusion: Taking advantage of GPU acceleration, we created a MC-based, biologically optimized treatment plan for a thyroid patient. Compared to a standard IMPT plan, a 5% increase in the target’s physical dose resulted in ∼3 times as much increase in the BD. Biological planning was thus effective in escalating the target BD.« less

  16. Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation

    NASA Astrophysics Data System (ADS)

    Magro, G.; Molinelli, S.; Mairani, A.; Mirandola, A.; Panizza, D.; Russo, S.; Ferrari, A.; Valvo, F.; Fossati, P.; Ciocca, M.

    2015-09-01

    This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5-30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo® TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus® chamber. An EBT3® film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification.

  17. Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation.

    PubMed

    Magro, G; Molinelli, S; Mairani, A; Mirandola, A; Panizza, D; Russo, S; Ferrari, A; Valvo, F; Fossati, P; Ciocca, M

    2015-09-07

    This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5-30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo(®) TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus(®) chamber. An EBT3(®) film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification.

  18. Optimum hot electron production with low-density foams for laser fusion by fast ignition.

    PubMed

    Lei, A L; Tanaka, K A; Kodama, R; Kumar, G R; Nagai, K; Norimatsu, T; Yabuuchi, T; Mima, K

    2006-06-30

    We propose a foam cone-in-shell target design aiming at optimum hot electron production for the fast ignition. A thin low-density foam is proposed to cover the inner tip of a gold cone inserted in a fuel shell. An intense laser is then focused on the foam to generate hot electrons for the fast ignition. Element experiments demonstrate increased laser energy coupling efficiency into hot electrons without increasing the electron temperature and beam divergence with foam coated targets in comparison with solid targets. This may enhance the laser energy deposition in the compressed fuel plasma.

  19. Projection-data based temporal maximum attenuation computed tomography: determination of internal target volume for lung cancer against intra-fraction motion

    NASA Astrophysics Data System (ADS)

    Mori, Shinichiro; Kanematsu, Nobuyuki; Asakura, Hiroshi; Endo, Masahiro

    2007-02-01

    The concept of internal target volume (ITV) is highly significant in radiotherapy for the lung, an organ which is hampered by organ motion. To date, different methods to obtain the ITV have been published and are therefore available. To define ITV, we developed a new method by adapting a time filter to the four-dimensional CT scan technique (4DCT) which is projection-data processing (4D projection data maximum attenuation (4DPM)), and compared it with reconstructed image processing (4D image maximum intensity projection (4DIM)) using a phantom and clinical evaluations. 4DIM and 4DPM captured accurate maximum intensity volume (MIV), that is tumour encompassing volume, easily. Although 4DIM increased the CT number 1.8 times higher than 4DPM, 4DPM provided the original tumour CT number for MIV via a reconstruction algorithm. In the patient with lung fibrosis honeycomb, the MIV with 4DIM is 0.7 cm larger than that for cine imaging in the cranio-caudal direction. 4DPM therefore provided an accurate MIV independent of patient characteristics and reconstruction conditions. These findings indicate the usefulness of 4DPM in determining ITV in radiotherapy.

  20. Fast reactor core concepts to improve transmutation efficiency

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fujimura, Koji; Kawashima, Katsuyuki; Itooka, Satoshi

    Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate.

  1. FAST: FAST Analysis of Sequences Toolbox

    PubMed Central

    Lawrence, Travis J.; Kauffman, Kyle T.; Amrine, Katherine C. H.; Carper, Dana L.; Lee, Raymond S.; Becich, Peter J.; Canales, Claudia J.; Ardell, David H.

    2015-01-01

    FAST (FAST Analysis of Sequences Toolbox) provides simple, powerful open source command-line tools to filter, transform, annotate and analyze biological sequence data. Modeled after the GNU (GNU's Not Unix) Textutils such as grep, cut, and tr, FAST tools such as fasgrep, fascut, and fastr make it easy to rapidly prototype expressive bioinformatic workflows in a compact and generic command vocabulary. Compact combinatorial encoding of data workflows with FAST commands can simplify the documentation and reproducibility of bioinformatic protocols, supporting better transparency in biological data science. Interface self-consistency and conformity with conventions of GNU, Matlab, Perl, BioPerl, R, and GenBank help make FAST easy and rewarding to learn. FAST automates numerical, taxonomic, and text-based sorting, selection and transformation of sequence records and alignment sites based on content, index ranges, descriptive tags, annotated features, and in-line calculated analytics, including composition and codon usage. Automated content- and feature-based extraction of sites and support for molecular population genetic statistics make FAST useful for molecular evolutionary analysis. FAST is portable, easy to install and secure thanks to the relative maturity of its Perl and BioPerl foundations, with stable releases posted to CPAN. Development as well as a publicly accessible Cookbook and Wiki are available on the FAST GitHub repository at https://github.com/tlawrence3/FAST. The default data exchange format in FAST is Multi-FastA (specifically, a restriction of BioPerl FastA format). Sanger and Illumina 1.8+ FastQ formatted files are also supported. FAST makes it easier for non-programmer biologists to interactively investigate and control biological data at the speed of thought. PMID:26042145

  2. Fast ion beta limit measurements by collimated neutron detection in MST plasmas

    NASA Astrophysics Data System (ADS)

    Capecchi, William; Anderson, Jay; Bonofiglo, Phillip; Kim, Jungha; Sears, Stephanie

    2015-11-01

    Fast ion orbits in the reversed field pinch (RFP) are well ordered and classically confined despite magnetic field stochasticity generated by multiple tearing modes. Classical TRANSP modeling of a 1MW tangentially injected hydrogen neutral beam in MST deuterium plasmas predicts a core-localized fast ion density that can be up to 25% of the electron density and a fast ion beta of many times the local thermal beta. However, neutral particle analysis of an NBI-driven mode (presumably driven by a fast ion pressure gradient) shows mode-induced transport of core-localized fast ions and a saturated fast ion density. The TRANSP modeling is presumed valid until the onset of the beam-driven mode and gives an initial estimate of the volume-averaged fast ion beta of 1-2% (local core value up to 10%). A collimated neutron detector for fusion product profile measurements will be used to determine the spatial distribution of fast ions, allowing for a first measurement of the critical fast-ion pressure gradient required for mode destabilization. Testing/calibration data and initial fast-ion profiles will be presented. Characterization of both the local and global fast ion beta will be done for deuterium beam injection into deuterium plasmas for comparison to TRANSP predictions. Work supported by US DOE.

  3. Are there benefits or harm from pressure targeting during lung-protective ventilation?

    PubMed

    MacIntyre, Neil R; Sessler, Curtis N

    2010-02-01

    Mechanically, breath design is usually either flow/volume-targeted or pressure-targeted. Both approaches can effectively provide lung-protective ventilation, but they prioritize different ventilation parameters, so their responses to changing respiratory-system mechanics and patient effort are different. These different response behaviors have advantages and disadvantages that can be important in specific circumstances. Flow/volume targeting guarantees a set minute ventilation but sometimes may be difficult to synchronize with patient effort, and it will not limit inspiratory pressure. In contrast, pressure targeting, with its variable flow, may be easier to synchronize and will limit inspiratory pressure, but it provides no control over delivered volume. Skilled clinicians can maximize benefits and minimize problems with either flow/volume targeting or pressure targeting. Indeed, as is often the case in managing complex life-support devices, it is operator expertise rather than the device design features that most impacts patient outcomes.

  4. Heterogeneity in TV fast food advertisement exposure in South Korea.

    PubMed

    Kim, Tae Hyun; Han, Euna; Jang, Sunmee

    2014-03-01

    To assess TV fast food ad exposure in South Korea. We assessed time trends of targeted ratings (licensed from Nielsen Media Research Korea) by household income and education during 2004-2010. Lower income groups saw more fast food TV ads during the study period. Exposure decreased in all income groups with a bigger income gap in 2010 than in 2004. The relative exposure to local fried chicken franchise TV ads surged from one fifth in 2004 to half of all TV fast food ads seen in 2010 in all socioeconomic status (SES). Future studies should assess the link between TV fast ood ad exposure, an important contextual factor for individual food choices, and actual consumption.

  5. Reproducibility of lung tumor position and reduction of lung mass within the planning target volume using active breathing control (ABC).

    PubMed

    Cheung, Patrick C F; Sixel, Katharina E; Tirona, Romeo; Ung, Yee C

    2003-12-01

    The active breathing control (ABC) device allows for temporary immobilization of respiratory motion by implementing a breath hold at a predefined relative lung volume and air flow direction. The purpose of this study was to quantitatively evaluate the ability of the ABC device to immobilize peripheral lung tumors at a reproducible position, increase total lung volume, and thereby reduce lung mass within the planning target volume (PTV). Ten patients with peripheral non-small-cell lung cancer tumors undergoing radiotherapy had CT scans of their thorax with and without ABC inspiration breath hold during the first 5 days of treatment. Total lung volumes were determined from the CT data sets. Each peripheral lung tumor was contoured by one physician on all CT scans to generate gross tumor volumes (GTVs). The lung density and mass contained within a 1.5-cm PTV margin around each peripheral tumor was calculated using CT numbers. Using the center of the GTV from the Day 1 ABC scan as the reference, the displacement of subsequent GTV centers on Days 2 to 5 for each patient with ABC applied was calculated in three dimensions. With the use of ABC inspiration breath hold, total lung volumes increased by an average of 42%. This resulted in an average decrease in lung mass of 18% within a standard 1.5-cm PTV margin around the GTV. The average (+/- standard deviation) displacement of GTV centers with ABC breath hold applied was 0.3 mm (+/- 1.8 mm), 1.2 mm (+/- 2.3 mm), and 1.1 mm (+/- 3.5 mm) in the lateral direction, anterior-posterior direction, and superior-inferior direction, respectively. Results from this study indicate that there remains some inter-breath hold variability in peripheral lung tumor position with the use of ABC inspiration breath hold, which prevents significant PTV margin reduction. However, lung volumes can significantly increase, thereby decreasing the mass of lung within a standard PTV.

  6. Rapid Microarray Detection of DNA and Proteins in Microliter Volumes with SPR Imaging Measurements

    PubMed Central

    Seefeld, Ting Hu; Zhou, Wen-Juan; Corn, Robert M.

    2011-01-01

    A four chamber microfluidic biochip is fabricated for the rapid detection of multiple proteins and nucleic acids from microliter volume samples with the technique of surface plasmon resonance imaging (SPRI). The 18 mm × 18 mm biochip consists of four 3 μL microfluidic chambers attached to an SF10 glass substrate, each of which contains three individually addressable SPRI gold thin film microarray elements. The twelve element (4 × 3) SPRI microarray consists of gold thin film spots (1 mm2 area; 45 nm thickness) each in individually addressable 0.5 μL volume microchannels. Microarrays of single-stranded DNA and RNA (ssDNA and ssRNA respectively) are fabricated by either chemical and/or enzymatic attachment reactions in these microchannels; the SPRI microarrays are then used to detect femtomole amounts (nanomolar concentrations) of DNA and proteins (single stranded DNA binding protein and thrombin via aptamer-protein bioaffinity interactions). Microarrays of ssRNA microarray elements were also used for the ultrasensitive detection of zeptomole amounts (femtomolar concentrations) of DNA via the technique of RNase H-amplified SPRI. Enzymatic removal of ssRNA from the surface due to the hybridization adsorption of target ssDNA is detected as a reflectivity decrease in the SPR imaging measurements. The observed reflectivity loss was proportional to the log of the target ssDNA concentration with a detection limit of 10 fM or 30 zeptomoles (18,000 molecules). This enzymatic amplified ssDNA detection method is not limited by diffusion of ssDNA to the interface, and thus is extremely fast, requiring only 200 seconds in the microliter volume format. PMID:21488682

  7. Technical Note: A fast online adaptive replanning method for VMAT using flattening filter free beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ates, Ozgur; Ahunbay, Ergun E.; Li, X. Allen, E-mail: ali@mcw.edu

    Purpose: To develop a fast replanning algorithm based on segment aperture morphing (SAM) for online replanning of volumetric modulated arc therapy (VMAT) with flattening filter free (FFF) beams. Methods: A software tool was developed to interface with a VMAT research planning system, which enables the input and output of beam and machine parameters of VMAT plans. The SAM algorithm was used to modify multileaf collimator positions for each segment aperture based on the changes of the target from the planning (CT/MR) to daily image [CT/CBCT/magnetic resonance imaging (MRI)]. The leaf travel distance was controlled for large shifts to prevent themore » increase of VMAT delivery time. The SAM algorithm was tested for 11 patient cases including prostate, pancreatic, and lung cancers. For each daily image set, three types of VMAT plans, image-guided radiation therapy (IGRT) repositioning, SAM adaptive, and full-scope reoptimization plans, were generated and compared. Results: The SAM adaptive plans were found to have improved the plan quality in target and/or critical organs when compared to the IGRT repositioning plans and were comparable to the reoptimization plans based on the data of planning target volume (PTV)-V100 (volume covered by 100% of prescription dose). For the cases studied, the average PTV-V100 was 98.85% ± 1.13%, 97.61% ± 1.45%, and 92.84% ± 1.61% with FFF beams for the reoptimization, SAM adaptive, and repositioning plans, respectively. The execution of the SAM algorithm takes less than 10 s using 16-CPU (2.6 GHz dual core) hardware. Conclusions: The SAM algorithm can generate adaptive VMAT plans using FFF beams with comparable plan qualities as those from the full-scope reoptimization plans based on daily CT/CBCT/MRI and can be used for online replanning to address interfractional variations.« less

  8. Aquaporins as Targets of Dietary Bioactive Phytocompounds

    PubMed Central

    Tesse, Angela; Grossini, Elena; Tamma, Grazia; Brenner, Catherine; Portincasa, Piero; Marinelli, Raul A.; Calamita, Giuseppe

    2018-01-01

    Plant-derived bioactive compounds have protective role for plants but may also modulate several physiological processes of plant consumers. In the last years, a wide spectrum of phytochemicals have been found to be beneficial to health interacting with molecular signaling pathways underlying critical functions such as cell growth and differentiation, apoptosis, autophagy, inflammation, redox balance, cell volume regulation, metabolic homeostasis, and energy balance. Hence, a large number of biologically active phytocompounds of foods have been isolated, characterized, and eventually modified representing a natural source of novel molecules to prevent, delay or cure several human diseases. Aquaporins (AQPs), a family of membrane channel proteins involved in many body functions, are emerging among the targets of bioactive phytochemicals in imparting their beneficial actions. Here, we provide a comprehensive review of this fast growing topic focusing especially on what it is known on the modulatory effects played by several edible plant and herbal compounds on AQPs, both in health and disease. Phytochemical modulation of AQP expression may provide new medical treatment options to improve the prognosis of several diseases. PMID:29721498

  9. Sodium levels in Canadian fast-food and sit-down restaurants.

    PubMed

    Scourboutakos, Mary J; L'Abbé, Mary R

    2013-01-31

    To evaluate the sodium levels in Canadian restaurant and fast-food chain menu items. Nutrition information was collected from the websites of major sit-down (n=20) and fast-food (n=65) restaurants across Canada in 2010 and a database was constructed. Four thousand and forty-four meal items, baked goods, side dishes and children's items were analyzed. Sodium levels were compared to the recommended adequate intake level (AI), tolerable upper intake level (UL) and the US National Sodium Reduction Initiative (NSRI) targets. On average, individual sit-down restaurant menu items contained 1455 mg sodium/serving (or 97% of the AI level of 1500 mg/day). Forty percent of all sit-down restaurant items exceeded the AI for sodium and more than 22% of sit-down restaurant stir fry entrées, sandwiches/wraps, ribs, and pasta entrées with meat/seafood exceeded the daily UL for sodium (2300 mg). Fast-food restaurant meal items contained, on average, 1011 mg sodium (68% of the daily AI), while side dishes (from sit-down and fast-food restaurants) contained 736 mg (49%). Children's meal items contained, on average, 790 mg/serving (66% of the sodium AI for children of 1200 mg/day); a small number of children's items exceeded the children's daily UL. On average, 52% of establishments exceeded the 2012 NSRI density targets and 69% exceeded the 2014 targets. The sodium content in Canadian restaurant foods is alarmingly high. A population-wide sodium reduction strategy needs to address the high levels of sodium in restaurant foods.

  10. Microstructure design for fast oxygen conduction

    DOE PAGES

    Aidhy, Dilpuneet S.; Weber, William J.

    2015-11-11

    Research from the last decade has shown that in designing fast oxygen conducting materials for electrochemical applications has largely shifted to microstructural features, in contrast to material-bulk. In particular, understanding oxygen energetics in heterointerface materials is currently at the forefront, where interfacial tensile strain is being considered as the key parameter in lowering oxygen migration barriers. Nanocrystalline materials with high densities of grain boundaries have also gathered interest that could possibly allow leverage over excess volume at grain boundaries, providing fast oxygen diffusion channels similar to those previously observed in metals. In addition, near-interface phase transformations and misfit dislocations aremore » other microstructural phenomenon/features that are being explored to provide faster diffusion. In this review, the current understanding on oxygen energetics, i.e., thermodynamics and kinetics, originating from these microstructural features is discussed. Moreover, our experimental observations, theoretical predictions and novel atomistic mechanisms relevant to oxygen transport are highlighted. In addition, the interaction of dopants with oxygen vacancies in the presence of these new microstructural features, and their future role in the design of future fast-ion conductors, is outlined.« less

  11. Controlling dynamics of imploded core plasma for fast ignition

    NASA Astrophysics Data System (ADS)

    Nagatomo, H.; Johzaki, T.; Sunahara, A.; Shiraga, H.; Sakagami, H.; Cai, H.; Mima, K.

    2010-08-01

    In the Fast ignition, formation of highly compressed core plasma is one of critical issue. In this work, the effect hydrodynamic instability in cone-guided shell implosion is studied. Two-dimensional radiation hydrodynamic simulations are carried out where realistic seeds of Rayleigh-Taylor instability are imposed. Preliminary results suggest that the instability reduces implosion performance, such as implosion velocity, areal density, and maximum density. In perturbed target implosion, the break-up time of the tip of the cone is earlier than that of ideal unperturbed target implosion case. This is crucial matter for the Fast ignition because the pass for the heating laser is filled with plasma before the shot of heating laser. A sophisticated implosion design of stable and low in-flight aspect ratio is necessary for cone-guided shell implosion.

  12. PALS Free Volume Measurements of Fractionated Hydrido- Silsesquioxane Resin.

    NASA Astrophysics Data System (ADS)

    Madani, Mahmoud M.; Granata, Richard D.; Pernisz, Udo C.

    1997-03-01

    Hydrido-Silsesquioxane (HSQ) is a resinous polymer with monomer unit formula (HSiO_3/2)_n. For n=8...16, it forms cages which in turn cross-link to yield a resin with a broad molecular weight distribution. It is soluble and forms thin films that may be converted to low-density silica with excellent dielectric properties. These, and the HSQ solubility, depend on molecular structure and size distribution of the cages. Samples of different molecular weight fractions were prepared from HSQ by SCF and the free volume of several cuts was measured by PALS in a conventional fast-fast system. POSITRONFIT and CONTIN programs were used to analyze the spectra. Three separate lifetime regions were identified with free volume regimes that correlate strongly with the molecular weight. The lowest is identified with the monomer cage unit, the larger values with intramolecular separation.

  13. Enabling fast charging – Battery thermal considerations

    DOE PAGES

    Keyser, Matthew; Pesaran, Ahmad; Li, Qibo; ...

    2017-10-23

    Battery thermal barriers are reviewed with regards to extreme fast charging. Present-day thermal management systems for battery electric vehicles are inadequate in limiting the maximum temperature rise of the battery during extreme fast charging. If the battery thermal management system is not designed correctly, the temperature of the cells could reach abuse temperatures and potentially send the cells into thermal runaway. Furthermore, the cell and battery interconnect design needs to be improved to meet the lifetime expectations of the consumer. Each of these aspects is explored and addressed as well as outlining where the heat is generated in a cell,more » the efficiencies of power and energy cells, and what type of battery thermal management solutions are available in today’s market. Here, thermal management is not a limiting condition with regard to extreme fast charging, but many factors need to be addressed especially for future high specific energy density cells to meet U.S. Department of Energy cost and volume goals.« less

  14. Enabling fast charging – Battery thermal considerations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keyser, Matthew; Pesaran, Ahmad; Li, Qibo

    Battery thermal barriers are reviewed with regards to extreme fast charging. Present-day thermal management systems for battery electric vehicles are inadequate in limiting the maximum temperature rise of the battery during extreme fast charging. If the battery thermal management system is not designed correctly, the temperature of the cells could reach abuse temperatures and potentially send the cells into thermal runaway. Furthermore, the cell and battery interconnect design needs to be improved to meet the lifetime expectations of the consumer. Each of these aspects is explored and addressed as well as outlining where the heat is generated in a cell,more » the efficiencies of power and energy cells, and what type of battery thermal management solutions are available in today’s market. Here, thermal management is not a limiting condition with regard to extreme fast charging, but many factors need to be addressed especially for future high specific energy density cells to meet U.S. Department of Energy cost and volume goals.« less

  15. Elective Clinical Target Volumes for Conformal Therapy in Anorectal Cancer: A Radiation Therapy Oncology Group Consensus Panel Contouring Atlas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Myerson, Robert J.; Garofalo, Michael C.; El Naqa, Issam

    2009-07-01

    Purpose: To develop a Radiation Therapy Oncology Group (RTOG) atlas of the elective clinical target volume (CTV) definitions to be used for planning pelvic intensity-modulated radiotherapy (IMRT) for anal and rectal cancers. Methods and Materials: The Gastrointestinal Committee of the RTOG established a task group (the nine physician co-authors) to develop this atlas. They responded to a questionnaire concerning three elective CTVs (CTVA: internal iliac, presacral, and perirectal nodal regions for both anal and rectal case planning; CTVB: external iliac nodal region for anal case planning and for selected rectal cases; CTVC: inguinal nodal region for anal case planning andmore » for select rectal cases), and to outline these areas on individual computed tomographic images. The imaging files were shared via the Advanced Technology Consortium. A program developed by one of the co-authors (I.E.N.) used binomial maximum-likelihood estimates to generate a 95% group consensus contour. The computer-estimated consensus contours were then reviewed by the group and modified to provide a final contouring consensus atlas. Results: The panel achieved consensus CTV definitions to be used as guidelines for the adjuvant therapy of rectal cancer and definitive therapy for anal cancer. The most important difference from similar atlases for gynecologic or genitourinary cancer is mesorectal coverage. Detailed target volume contouring guidelines and images are discussed. Conclusion: This report serves as a template for the definition of the elective CTVs to be used in IMRT planning for anal and rectal cancers, as part of prospective RTOG trials.« less

  16. Formulation Assessment and Support Team (FAST) for the Asteroid Redirect Mission (ARM)

    NASA Astrophysics Data System (ADS)

    Mazanek, Daniel D.; Abell, Paul; Reeves, David M.; NASA Asteroid Redirect Mission (ARM) Formulation Assessment and Support Team (FAST)

    2016-10-01

    The Formulation Assessment and Support Team (FAST) for the Asteroid Redirect Mission (ARM) was a two-month effort, chartered by NASA, to provide timely inputs for mission requirement formulation in support of the Asteroid Redirect Robotic Mission (ARRM) Requirements Closure Technical Interchange Meeting held December 15-16, 2015. Additionally, the FAST was tasked with developing an initial list of potential mission investigations and providing input on potential hosted payloads and partnerships. The FAST explored several aspects of potential science benefits and knowledge gain from the ARM. Expertise from the science, engineering, and technology communities was represented in exploring lines of inquiry related to key characteristics of the ARRM reference target asteroid (2008 EV5) for engineering design purposes. Specific areas of interest included target origin, spatial distribution and size of boulders, surface geotechnical properties, boulder physical properties, and considerations for boulder handling, crew safety, and containment. In order to increase knowledge gain potential from the mission, opportunities for partnerships and accompanying payloads that could be provided by domestic and international partners were also investigated. The ARM FAST final report was publicly released on February 18, 2016 and represents the FAST's final product. The report and associated public comments are being used to support mission requirements formulation and serve as an initial inquiry to the science and engineering communities relating to the characteristics of the ARRM reference target asteroid. This report also provides a suggested list of potential investigations sorted and grouped based on their likely benefit to ARM and potential relevance to NASA science and exploration goals. These potential investigations could be conducted to reduce mission risks and increase knowledge return in the areas of science, planetary defense, asteroid resources and in-situ resource

  17. The dosimetric impact of daily setup error on target volumes and surrounding normal tissue in the treatment of prostate cancer with intensity-modulated radiation therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Algan, Ozer, E-mail: oalgan@ouhsc.edu; Jamgade, Ambarish; Ali, Imad

    2012-01-01

    The purpose of this study was to evaluate the impact of daily setup error and interfraction organ motion on the overall dosimetric radiation treatment plans. Twelve patients undergoing definitive intensity-modulated radiation therapy (IMRT) treatments for prostate cancer were evaluated in this institutional review board-approved study. Each patient had fiducial markers placed into the prostate gland before treatment planning computed tomography scan. IMRT plans were generated using the Eclipse treatment planning system. Each patient was treated to a dose of 8100 cGy given in 45 fractions. In this study, we retrospectively created a plan for each treatment day that had amore » shift available. To calculate the dose, the patient would have received under this plan, we mathematically 'negated' the shift by moving the isocenter in the exact opposite direction of the shift. The individualized daily plans were combined to generate an overall plan sum. The dose distributions from these plans were compared with the treatment plans that were used to treat the patients. Three-hundred ninety daily shifts were negated and their corresponding plans evaluated. The mean isocenter shift based on the location of the fiducial markers was 3.3 {+-} 6.5 mm to the right, 1.6 {+-} 5.1 mm posteriorly, and 1.0 {+-} 5.0 mm along the caudal direction. The mean D95 doses for the prostate gland when setup error was corrected and uncorrected were 8228 and 7844 cGy (p < 0.002), respectively, and for the planning target volume (PTV8100) was 8089 and 7303 cGy (p < 0.001), respectively. The mean V95 values when patient setup was corrected and uncorrected were 99.9% and 87.3%, respectively, for the PTV8100 volume (p < 0.0001). At an individual patient level, the difference in the D95 value for the prostate volume could be >1200 cGy and for the PTV8100 could approach almost 2000 cGy when comparing corrected against uncorrected plans. There was no statistically significant difference in the D35

  18. Multimodal Hierarchical Imaging of Serial Sections for Finding Specific Cellular Targets within Large Volumes

    PubMed Central

    Wacker, Irene U.; Veith, Lisa; Spomer, Waldemar; Hofmann, Andreas; Thaler, Marlene; Hillmer, Stefan; Gengenbach, Ulrich; Schröder, Rasmus R.

    2018-01-01

    Targeting specific cells at ultrastructural resolution within a mixed cell population or a tissue can be achieved by hierarchical imaging using a combination of light and electron microscopy. Samples embedded in resin are sectioned into arrays consisting of ribbons of hundreds of ultrathin sections and deposited on pieces of silicon wafer or conductively coated coverslips. Arrays are imaged at low resolution using a digital consumer like smartphone camera or light microscope (LM) for a rapid large area overview, or a wide field fluorescence microscope (fluorescence light microscopy (FLM)) after labeling with fluorophores. After post-staining with heavy metals, arrays are imaged in a scanning electron microscope (SEM). Selection of targets is possible from 3D reconstructions generated by FLM or from 3D reconstructions made from the SEM image stacks at intermediate resolution if no fluorescent markers are available. For ultrastructural analysis, selected targets are finally recorded in the SEM at high-resolution (a few nanometer image pixels). A ribbon-handling tool that can be retrofitted to any ultramicrotome is demonstrated. It helps with array production and substrate removal from the sectioning knife boat. A software platform that allows automated imaging of arrays in the SEM is discussed. Compared to other methods generating large volume EM data, such as serial block-face SEM (SBF-SEM) or focused ion beam SEM (FIB-SEM), this approach has two major advantages: (1) The resin-embedded sample is conserved, albeit in a sliced-up version. It can be stained in different ways and imaged with different resolutions. (2) As the sections can be post-stained, it is not necessary to use samples strongly block-stained with heavy metals to introduce contrast for SEM imaging or render the tissue blocks conductive. This makes the method applicable to a wide variety of materials and biological questions. Particularly prefixed materials e.g., from biopsy banks and pathology labs

  19. A method to combine target volume data from 3D and 4D planned thoracic radiotherapy patient cohorts for machine learning applications.

    PubMed

    Johnson, Corinne; Price, Gareth; Khalifa, Jonathan; Faivre-Finn, Corinne; Dekker, Andre; Moore, Christopher; van Herk, Marcel

    2018-02-01

    The gross tumour volume (GTV) is predictive of clinical outcome and consequently features in many machine-learned models. 4D-planning, however, has prompted substitution of the GTV with the internal gross target volume (iGTV). We present and validate a method to synthesise GTV data from the iGTV, allowing the combination of 3D and 4D planned patient cohorts for modelling. Expert delineations in 40 non-small cell lung cancer patients were used to develop linear fit and erosion methods to synthesise the GTV volume and shape. Quality was assessed using Dice Similarity Coefficients (DSC) and closest point measurements; by calculating dosimetric features; and by assessing the quality of random forest models built on patient populations with and without synthetic GTVs. Volume estimates were within the magnitudes of inter-observer delineation variability. Shape comparisons produced mean DSCs of 0.8817 and 0.8584 for upper and lower lobe cases, respectively. A model trained on combined true and synthetic data performed significantly better than models trained on GTV alone, or combined GTV and iGTV data. Accurate synthesis of GTV size from the iGTV permits the combination of lung cancer patient cohorts, facilitating machine learning applications in thoracic radiotherapy. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Target volume definition for 18F-FDG PET-positive lymph nodes in radiotherapy of patients with non-small cell lung cancer.

    PubMed

    Nestle, Ursula; Schaefer-Schuler, Andrea; Kremp, Stephanie; Groeschel, Andreas; Hellwig, Dirk; Rübe, Christian; Kirsch, Carl-Martin

    2007-04-01

    FDG PET is increasingly used in radiotherapy planning. Recently, we demonstrated substantial differences in target volumes when applying different methods of FDG-based contouring in primary lung tumours (Nestle et al., J Nucl Med 2005;46:1342-8). This paper focusses on FDG-positive mediastinal lymph nodes (LN(PET)). In our institution, 51 NSCLC patients who were candidates for radiotherapy prospectively underwent staging FDG PET followed by a thoracic PET scan in the treatment position and a planning CT. Eleven of them had 32 distinguishable non-confluent mediastinal or hilar nodal FDG accumulations (LN(PET)). For these, sets of gross tumour volumes (GTVs) were generated at both acquisition times by four different PET-based contouring methods (visual: GTV(vis); 40% SUVmax: GTV40; SUV=2.5: GTV2.5; target/background (T/B) algorithm: GTV(bg)). All differences concerning GTV sizes were within the range of the resolution of the PET system. The detectability and technical delineability of the GTVs were significantly better in the late scans (e.g. p = 0.02 for diagnostic application of SUVmax = 2.5; p = 0.0001 for technical delineability by GTV2.5; p = 0.003 by GTV40), favouring the GTV(bg) method owing to satisfactory overall applicability and independence of GTVs from acquisition time. Compared with CT, the majority of PET-based GTVs were larger, probably owing to resolution effects, with a possible influence of lesion movements. For nodal GTVs, different methods of contouring did not lead to clinically relevant differences in volumes. However, there were significant differences in technical delineability, especially after early acquisition. Overall, our data favour a late acquisition of FDG PET scans for radiotherapy planning, and the use of a T/B algorithm for GTV contouring.

  1. A standardized evaluation of artefacts from metallic compounds during fast MR imaging

    PubMed Central

    Murakami, Shumei; Kataoka, Miyoshi; Kakimoto, Naoya; Shimamoto, Hiroaki; Kreiborg, Sven

    2016-01-01

    Objectives: Metallic compounds present in the oral and maxillofacial regions (OMRs) cause large artefacts during MR scanning. We quantitatively assessed these artefacts embedded within a phantom according to standards set by the American Society for Testing and Materials (ASTM). Methods: Seven metallic dental materials (each of which was a 10-mm3 cube embedded within a phantom) were scanned [i.e. aluminium (Al), silver alloy (Ag), type IV gold alloy (Au), gold–palladium–silver alloy (Au-Pd-Ag), titanium (Ti), nickel–chromium alloy (NC) and cobalt–chromium alloy (CC)] and compared with a reference image. Sequences included gradient echo (GRE), fast spin echo (FSE), gradient recalled acquisition in steady state (GRASS), a spoiled GRASS (SPGR), a fast SPGR (FSPGR), fast imaging employing steady state (FIESTA) and echo planar imaging (EPI; axial/sagittal planes). Artefact areas were determined according to the ASTM-F2119 standard, and artefact volumes were assessed using OsiriX MD software (Pixmeo, Geneva, Switzerland). Results: Tukey–Kramer post hoc tests were used for statistical comparisons. For most materials, scanning sequences eliciting artefact volumes in the following (ascending) order FSE-T1/FSE-T2 < FSPGR/SPGR < GRASS/GRE < FIESTA < EPI. For all scanning sequences, artefact volumes containing Au, Al, Ag and Au-Pd-Ag were significantly smaller than other materials (in which artefact volume size increased, respectively, from Ti < NC < CC). The artefact-specific shape (elicited by the cubic sample) depended on the scanning plane (i.e. a circular pattern for the axial plane and a “clover-like” pattern for the sagittal plane). Conclusions: The availability of standardized information on artefact size and configuration during MRI will enhance diagnosis when faced with metallic compounds in the OMR. PMID:27459058

  2. Comparison of fasting and non-fasting lipid profiles in a large cohort of patients presenting at a community hospital.

    PubMed

    Cartier, Louis-Jacques; Collins, Charlene; Lagacé, Mathieu; Douville, Pierre

    2018-02-01

    To compare the fasting and non-fasting lipid profile including ApoB in a cohort of patients from a community setting. Our purpose was to determine the proportion of results that could be explained by the known biological variation in the fasting state and to examine the additional impact of non-fasting on these same lipid parameters. 1093 adult outpatients with fasting lipid requests were recruited from February to September 2016 at the blood collection sites of the Moncton Hospital. Participants were asked to come back in the next 3-4days after having eaten a regular breakfast to have their blood drawn for a non-fasting lipid profile. 91.6% of patients in this study had a change in total cholesterol that fell within the biological variation expected for this parameter. Similar results were seen for HDL-C (94.3%) non-HDL-C (88.8%) and ApoB (93.0%). A smaller number of patients fell within the biological variation expected for TG (78.8%) and LDL-C (74.6%). An average TG increase of 0.3mmol/L was observed in fed patients no matter the level of fasting TG. A gradual widening in the range of change in TG concentration was observed as fasting TG increased. Similar results were seen in diabetic patients. Outside of LDL-C and TG, little changes were seen in lipid parameters in the postprandial state. A large part of these changes could be explained by the biological variation. We observed a gradual widening in the range of increase in TG for patients with higher fasting TG. Non-HDL-C and ApoB should be the treatment target of choice for patients in the non-fasting state. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  3. Fast High Resolution Volume Carving for 3D Plant Shoot Reconstruction

    PubMed Central

    Scharr, Hanno; Briese, Christoph; Embgenbroich, Patrick; Fischbach, Andreas; Fiorani, Fabio; Müller-Linow, Mark

    2017-01-01

    Volume carving is a well established method for visual hull reconstruction and has been successfully applied in plant phenotyping, especially for 3d reconstruction of small plants and seeds. When imaging larger plants at still relatively high spatial resolution (≤1 mm), well known implementations become slow or have prohibitively large memory needs. Here we present and evaluate a computationally efficient algorithm for volume carving, allowing e.g., 3D reconstruction of plant shoots. It combines a well-known multi-grid representation called “Octree” with an efficient image region integration scheme called “Integral image.” Speedup with respect to less efficient octree implementations is about 2 orders of magnitude, due to the introduced refinement strategy “Mark and refine.” Speedup is about a factor 1.6 compared to a highly optimized GPU implementation using equidistant voxel grids, even without using any parallelization. We demonstrate the application of this method for trait derivation of banana and maize plants. PMID:29033961

  4. Silence of synaptotagmin I in INS-1 cells inhibits fast exocytosis and fast endocytosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiong Xiong; Zhou Keming; Wu Zhengxing

    Synaptotagmin I (Syt I) is a Ca{sup 2+} sensor for triggering fast synchronized release of neurotransmitters. However, controversy remains whether Syt I is also obligatory for the exocytosis and endocytosis of larger dense core vesicles (LDCVs) in endocrine cells. In this study, we used a short hairpin RNA (shRNA) to silence the expression of Syt I and investigated the roles of Syt I on exocytosis and endocytosis in INS-1 cells. Our results demonstrated that expression of Syt I is remarkably reduced by the Syt I gene targeting shRNA. Using high-time resolution capacitance measurement, we found that the silence of Sytmore » I decreased the calcium sensitivity of fusion of insulin granules and therefore reduced the exocytotic burst triggered by step-like [Ca{sup 2+}] {sub i} elevation. In addition, the occurrence frequency and amplitude of fast endocytosis were remarkably reduced in the silenced cells. We conclude that Syt I not only participates in the Ca{sup 2+}-sensing of LDCV fusion with plasmalemma, but also plays a crucial role in fast endocytosis in INS-1 cells.« less

  5. Effect of Fasting on Corneal Biomechanical and Structural Parameters.

    PubMed

    Sarici, Ahmet M; Yuksel Elgin, Cansu; Dikkaya, Funda

    2016-07-01

    To evaluate the effects of hunger and thirst on corneal biomechanical and structural parameters during Ramadan fasting. Corneal biomechanical properties and intraocular pressures of 29 eyes of 29 healthy subjects were evaluated by Reichert ocular response analyzer; and structural and anatomical properties of cornea and anterior eye chamber of same eyes were scanned with Oculus Pentacam anterior segment analyzer. Each eye has been evaluated at 8 am and 4 pm both during and 1 month after Ramadan. Changes of subjects' weight were calculated and their relationship with corneal biomechanical and structural parameters was assessed. Intraday changes in horizontal corneal astigmatism (p = 0.02), anterior chamber volume (p = 0.01), intraocular pressure associated with the Goldmann IOPg (p = 0.02) and corneal resistance factor (CRF) (p = 0.04) were significantly different when measured during the fasting period in Ramadan and 1 month thereafter. Moreover, when we compared 8 am measurements taken during and after Ramadan, we observed significant differences for anterior chamber volume (p = 0.04) and anterior chamber angle values (p = 0.03). Similarly, for 4 pm measurements, there were significant differences for IOPg (p = 0.01) and CRF values (p = 0.00). Fasting lasting for more than 12 h during Ramadan creates an important window of opportunity to investigate the response of anterior chamber of eye to hunger and thirst. The current study contributes to the existing literature on the effects of dietary habits and water intake on corneal and anterior chamber properties.

  6. Functional Requirements of a Target Description System for Vulnerability Analysis

    DTIC Science & Technology

    1979-11-01

    called GIFT .1,2 Together the COMGEOM description model and GIFT codes make up the BRL’s target description system. The significance of a target...and modifying target descriptions are described. 1 Lawrence W. Bain, Jr. and Mathew J. Reisinger, "The GIFT Code User Manual; Volume 1...34The GIFT Code User Manual; Volume II, The Output Options," unpublished draft of BRL report. II. UNDERLYING PHILOSOPHY The BRL has a computer

  7. Does hydration status affect MRI measures of brain volume or water content?

    PubMed

    Meyers, Sandra M; Tam, Roger; Lee, Jimmy S; Kolind, Shannon H; Vavasour, Irene M; Mackie, Emilie; Zhao, Yinshan; Laule, Cornelia; Mädler, Burkhard; Li, David K B; MacKay, Alex L; Traboulsee, Anthony L

    2016-08-01

    To determine whether differences in hydration state, which could arise from routine clinical procedures such as overnight fasting, affect brain total water content (TWC) and brain volume measured with magnetic resonance imaging (MRI). Twenty healthy volunteers were scanned with a 3T MR scanner four times: day 1, baseline scan; day 2, hydrated scan after consuming 3L of water over 12 hours; day 3, dehydrated scan after overnight fasting of 9 hours, followed by another scan 1 hour later for reproducibility. The following MRI data were collected: T2 relaxation (for TWC measurement), inversion recovery (for T1 measurement), and 3D T1 -weighted (for brain volumes). Body weight and urine specific gravity were also measured. TWC was calculated by fitting the T2 relaxation data with a nonnegative least-squares algorithm, with corrections for T1 relaxation and image signal inhomogeneity and normalization to ventricular cerebrospinal fluid. Brain volume changes were measured using SIENA. TWC means were calculated within 14 tissue regions. Despite indications of dehydration as demonstrated by increases in urine specific gravity (P = 0.03) and decreases in body weight (P = 0.001) between hydrated and dehydrated scans, there was no measurable change in TWC (within any brain region) or brain volume between hydration states. We demonstrate that within a range of physiologic conditions commonly encountered in routine clinical scans (no pretreatment with hydration, well hydrated before MRI, and overnight fasting), brain TWC and brain volumes are not substantially affected in a healthy control cohort. J. Magn. Reson. Imaging 2016;44:296-304. © 2016 Wiley Periodicals, Inc.

  8. Determination of internal target volume for radiation treatment planning of esophageal cancer by using 4-dimensional computed tomography (4DCT).

    PubMed

    Chen, Xiaojian; Lu, Haijun; Tai, An; Johnstone, Candice; Gore, Elizabeth; Li, X Allen

    2014-09-01

    To determine an efficient strategy for the generation of the internal target volume (ITV) for radiation treatment planning for esophageal cancer using 4-dimensional computed tomography (4DCT). 4DCT sets acquired for 20 patients with esophageal carcinoma were analyzed. Each of the 4DCT sets was binned into 10 respiratory phases. For each patient, the gross tumor volume (GTV) was delineated on the 4DCT set at each phase. Various strategies to derive ITV were explored, including the volume from the maximum intensity projection (MIP; ITV_MIP), unions of the GTVs from selected multiple phases ITV2 (0% and 50% phases), ITV3 (ITV2 plus 80%), and ITV4 (ITV3 plus 60%), as well as the volumes expanded from ITV2 and ITV3 with a uniform margin. These ITVs were compared to ITV10 (the union of the GTVs for all 10 phases) and the differences were measured with the overlap ratio (OR) and relative volume ratio (RVR) relative to ITV10 (ITVx/ITV10). For all patients studied, the average GTV from a single phase was 84.9% of ITV10. The average ORs were 91.2%, 91.3%, 94.5%, and 96.4% for ITV_MIP, ITV2, ITV3, and ITV4, respectively. Low ORs were associated with irregular breathing patterns. ITV3s plus 1 mm uniform margins (ITV3+1) led to an average OR of 98.1% and an average RVR of 106.4%. The ITV generated directly from MIP underestimates the range of the respiration motion for esophageal cancer. The ITV generated from 3 phases (ITV3) may be used for regular breathers, whereas the ITV generated from 4 phases (ITV4) or ITV3 plus a 1-mm uniform margin may be applied for irregular breathers. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Effects of winter fasting and refeeding on white-tailed deer blood profiles

    USGS Publications Warehouse

    DelGiudice, G.D.; Mech, L.D.; Seal, U.S.; Karns, P.D.

    1987-01-01

    This study examined the effects of dietary protein, fasting, and refeeding on blood characteristics of 9 nonpregnant, female white-tailed deer (Odocoileus virginianus) in captivity from 23 February to 3 May 1984. Percent weight loss was greater in fasted deer than in deer fed diets of 2 crude protein levels. Fasting effects were also observed for hemoglobin (Hb), red blood cell (RBC) counts, packed cell volume (PCV), cholesterol, triglycerides, serum urea nitrogen (SUN), potassium (K), glucose, phosphorus (P), insulin, thyroxine (T4), and total protein (TP). Refeeding influenced cholesterol, sodium (Na), and calcium (Ca). Hemoglobin, PCV, Ca, P, and albumin varied with time in fasted deer. Changes over time in the fed deer occurred for several hematological and serum characteristics. Data are presented to serve as reference values for better understanding of data collected from free-ranging deer under less known conditions.

  10. Efficient monoenergetic proton beam from ultra-fast laser interaction with nanostructured targets

    NASA Astrophysics Data System (ADS)

    Fazeli, R.

    2018-03-01

    The broad energy spectrum of laser-accelerated proton beams is the most important difficulty associated with such particle sources on the way to future applications such as medical therapy, proton imaging, inertial fusion, and high-energy physics. The generation of proton beams with enhanced monoenergetic features through an ultra-intense laser interaction with optimized nanostructured targets is reported. Targets were irradiated by 40 fs laser pulses of intensity 5.5 ×1020 W c m -2 and wavelength 1 μm. The results of multi-parametric Particle-in-Cell calculations showed that proton beams with considerably reduced energy spread can be obtained by using the proposed nanostructured target. At optimized target dimensions, the proton spectrum was found to exhibit a narrow peak at about 63 MeV with a relative energy spread of ΔE /Epeak˜ 5 % which is efficiently lower than what is expected for unstructured double layer targets (˜70%).

  11. Dosimetric evaluation of planning target volume margin reduction for prostate cancer via image-guided intensity-modulated radiation therapy

    NASA Astrophysics Data System (ADS)

    Hwang, Taejin; Kang, Sei-Kwon; Cheong, Kwang-Ho; Park, Soah; Yoon, Jai-Woong; Han, Taejin; Kim, Haeyoung; Lee, Meyeon; Kim, Kyoung-Joo; Bae, Hoonsik; Suh, Tae-Suk

    2015-07-01

    The aim of this study was to quantitatively estimate the dosimetric benefits of the image-guided radiation therapy (IGRT) system for the prostate intensity-modulated radiation therapy (IMRT) delivery. The cases of eleven patients who underwent IMRT for prostate cancer without a prostatectomy at our institution between October 2012 and April 2014 were retrospectively analyzed. For every patient, clinical target volume (CTV) to planning target volume (PTV) margins were uniformly used: 3 mm, 5 mm, 7 mm, 10 mm, 12 mm, and 15 mm. For each margin size, the IMRT plans were independently optimized by one medical physicist using Pinnalce3 (ver. 8.0.d, Philips Medical System, Madison, WI) in order to maintain the plan quality. The maximum geometrical margin (MGM) for every CT image set, defined as the smallest margin encompassing the rectum at least at one slice, was between 13 mm and 26 mm. The percentage rectum overlapping PTV (%V ROV ), the rectal normal tissue complication probability (NTCP) and the mean rectal dose (%RD mean ) increased in proportion to the increase of PTV margin. However the bladder NTCP remained around zero to some extent regardless of the increase of PTV margin while the percentage bladder overlapping PTV (%V BOV ) and the mean bladder dose (%BD mean ) increased in proportion to the increase of PTV margin. Without relatively large rectum or small bladder, the increase observed for rectal NTCP, %RDmean and %BD mean per 1-mm PTV margin size were 1.84%, 2.44% and 2.90%, respectively. Unlike the behavior of the rectum or the bladder, the maximum dose on each femoral head had little effect on PTV margin. This quantitative study of the PTV margin reduction supported that IG-IMRT has enhanced the clinical effects over prostate cancer with the reduction of normal organ complications under the similar level of PTV control.

  12. Detection of Fast Moving and Accelerating Targets Compensating Range and Doppler Migration

    DTIC Science & Technology

    2014-06-01

    Radon -Fourier transform has been introduced to realize long- term coherent integration of the moving targets with range migration [8, 9]. Radon ...2010) Long-time coherent integration for radar target detection base on Radon -Fourier transform, in Proceedings of the IEEE Radar Conference, pp...432–436. 9. Xu, J., Yu, J., Peng, Y. & Xia, X. (2011) Radon -Fourier transform for radar target detection, I: Generalized Doppler filter bank, IEEE

  13. The effect of irregular breathing patterns on internal target volumes in four-dimensional CT and cone-beam CT images in the context of stereotactic lung radiotherapy.

    PubMed

    Clements, N; Kron, T; Franich, R; Dunn, L; Roxby, P; Aarons, Y; Chesson, B; Siva, S; Duplan, D; Ball, D

    2013-02-01

    Stereotactic lung radiotherapy is complicated by tumor motion from patient respiration. Four-dimensional CT (4DCT) imaging is a motion compensation method used in treatment planning to generate a maximum intensity projection (MIP) internal target volume (ITV). Image guided radiotherapy during treatment may involve acquiring a volumetric cone-beam CT (CBCT) image and visually aligning the tumor to the planning 4DCT MIP ITV contour. Moving targets imaged with CBCT can appear blurred and currently there are no studies reporting on the effect that irregular breathing patterns have on CBCT volumes and their alignment to 4DCT MIP ITV contours. The objective of this work was therefore to image a phantom moving with irregular breathing patterns to determine whether any configurations resulted in errors in volume contouring or alignment. A Perspex thorax phantom was used to simulate a patient. Three wooden "lung" inserts with embedded Perspex "lesions" were moved up to 4 cm with computer-generated motion patterns, and up to 1 cm with patient-specific breathing patterns. The phantom was imaged on 4DCT and CBCT with the same acquisition settings used for stereotactic lung patients in the clinic and the volumes on all phantom images were contoured. This project assessed the volumes for qualitative and quantitative changes including volume, length of the volume, and errors in alignment between CBCT volumes and 4DCT MIP ITV contours. When motion was introduced 4DCT and CBCT volumes were reduced by up to 20% and 30% and shortened by up to 7 and 11 mm, respectively, indicating that volume was being under-represented at the extremes of motion. Banding artifacts were present in 4DCT MIP images, while CBCT volumes were largely reduced in contrast. When variable amplitudes from patient traces were used and CBCT ITVs were compared to 4DCT MIP ITVs there was a distinct trend in reduced ITV with increasing amplitude that was not seen when compared to true ITVs. Breathing patterns with a

  14. The effect of irregular breathing patterns on internal target volumes in four-dimensional CT and cone-beam CT images in the context of stereotactic lung radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clements, N.; Kron, T.; Roxby, P.

    2013-02-15

    Purpose: Stereotactic lung radiotherapy is complicated by tumor motion from patient respiration. Four-dimensional CT (4DCT) imaging is a motion compensation method used in treatment planning to generate a maximum intensity projection (MIP) internal target volume (ITV). Image guided radiotherapy during treatment may involve acquiring a volumetric cone-beam CT (CBCT) image and visually aligning the tumor to the planning 4DCT MIP ITV contour. Moving targets imaged with CBCT can appear blurred and currently there are no studies reporting on the effect that irregular breathing patterns have on CBCT volumes and their alignment to 4DCT MIP ITV contours. The objective of thismore » work was therefore to image a phantom moving with irregular breathing patterns to determine whether any configurations resulted in errors in volume contouring or alignment. Methods: A Perspex thorax phantom was used to simulate a patient. Three wooden 'lung' inserts with embedded Perspex 'lesions' were moved up to 4 cm with computer-generated motion patterns, and up to 1 cm with patient-specific breathing patterns. The phantom was imaged on 4DCT and CBCT with the same acquisition settings used for stereotactic lung patients in the clinic and the volumes on all phantom images were contoured. This project assessed the volumes for qualitative and quantitative changes including volume, length of the volume, and errors in alignment between CBCT volumes and 4DCT MIP ITV contours. Results: When motion was introduced 4DCT and CBCT volumes were reduced by up to 20% and 30% and shortened by up to 7 and 11 mm, respectively, indicating that volume was being under-represented at the extremes of motion. Banding artifacts were present in 4DCT MIP images, while CBCT volumes were largely reduced in contrast. When variable amplitudes from patient traces were used and CBCT ITVs were compared to 4DCT MIP ITVs there was a distinct trend in reduced ITV with increasing amplitude that was not seen when compared to

  15. Radioactive waste from decommissioning of fast reactors (through the example of BN-800)

    NASA Astrophysics Data System (ADS)

    Rybin, A. A.; Momot, O. A.

    2017-01-01

    Estimation of volume of radioactive waste from operating and decommissioning of fast reactors is introduced. Preliminary estimation has shown that the volume of RW from decommissioning of BN-800 is amounted to 63,000 cu. m. Comparison of the amount of liquid radioactive waste derived from operation of different reactor types is performed. Approximate costs of all wastes disposal for complete decommissioning of BN-800 reactor are estimated amounting up to approx. 145 million.

  16. Impact of PET and MRI threshold-based tumor volume segmentation on patient-specific targeted radionuclide therapy dosimetry using CLR1404.

    PubMed

    Besemer, Abigail E; Titz, Benjamin; Grudzinski, Joseph J; Weichert, Jamey P; Kuo, John S; Robins, H Ian; Hall, Lance T; Bednarz, Bryan P

    2017-07-06

    Variations in tumor volume segmentation methods in targeted radionuclide therapy (TRT) may lead to dosimetric uncertainties. This work investigates the impact of PET and MRI threshold-based tumor segmentation on TRT dosimetry in patients with primary and metastatic brain tumors. In this study, PET/CT images of five brain cancer patients were acquired at 6, 24, and 48 h post-injection of 124 I-CLR1404. The tumor volume was segmented using two standardized uptake value (SUV) threshold levels, two tumor-to-background ratio (TBR) threshold levels, and a T1 Gadolinium-enhanced MRI threshold. The dice similarity coefficient (DSC), jaccard similarity coefficient (JSC), and overlap volume (OV) metrics were calculated to compare differences in the MRI and PET contours. The therapeutic 131 I-CLR1404 voxel-level dose distribution was calculated from the 124 I-CLR1404 activity distribution using RAPID, a Geant4 Monte Carlo internal dosimetry platform. The TBR, SUV, and MRI tumor volumes ranged from 2.3-63.9 cc, 0.1-34.7 cc, and 0.4-11.8 cc, respectively. The average  ±  standard deviation (range) was 0.19  ±  0.13 (0.01-0.51), 0.30  ±  0.17 (0.03-0.67), and 0.75  ±  0.29 (0.05-1.00) for the JSC, DSC, and OV, respectively. The DSC and JSC values were small and the OV values were large for both the MRI-SUV and MRI-TBR combinations because the regions of PET uptake were generally larger than the MRI enhancement. Notable differences in the tumor dose volume histograms were observed for each patient. The mean (standard deviation) 131 I-CLR1404 tumor doses ranged from 0.28-1.75 Gy GBq -1 (0.07-0.37 Gy GBq -1 ). The ratio of maximum-to-minimum mean doses for each patient ranged from 1.4-2.0. The tumor volume and the interpretation of the tumor dose is highly sensitive to the imaging modality, PET enhancement metric, and threshold level used for tumor volume segmentation. The large variations in tumor doses clearly demonstrate the need for

  17. Impact of PET and MRI threshold-based tumor volume segmentation on patient-specific targeted radionuclide therapy dosimetry using CLR1404

    NASA Astrophysics Data System (ADS)

    Besemer, Abigail E.; Titz, Benjamin; Grudzinski, Joseph J.; Weichert, Jamey P.; Kuo, John S.; Robins, H. Ian; Hall, Lance T.; Bednarz, Bryan P.

    2017-08-01

    Variations in tumor volume segmentation methods in targeted radionuclide therapy (TRT) may lead to dosimetric uncertainties. This work investigates the impact of PET and MRI threshold-based tumor segmentation on TRT dosimetry in patients with primary and metastatic brain tumors. In this study, PET/CT images of five brain cancer patients were acquired at 6, 24, and 48 h post-injection of 124I-CLR1404. The tumor volume was segmented using two standardized uptake value (SUV) threshold levels, two tumor-to-background ratio (TBR) threshold levels, and a T1 Gadolinium-enhanced MRI threshold. The dice similarity coefficient (DSC), jaccard similarity coefficient (JSC), and overlap volume (OV) metrics were calculated to compare differences in the MRI and PET contours. The therapeutic 131I-CLR1404 voxel-level dose distribution was calculated from the 124I-CLR1404 activity distribution using RAPID, a Geant4 Monte Carlo internal dosimetry platform. The TBR, SUV, and MRI tumor volumes ranged from 2.3-63.9 cc, 0.1-34.7 cc, and 0.4-11.8 cc, respectively. The average  ±  standard deviation (range) was 0.19  ±  0.13 (0.01-0.51), 0.30  ±  0.17 (0.03-0.67), and 0.75  ±  0.29 (0.05-1.00) for the JSC, DSC, and OV, respectively. The DSC and JSC values were small and the OV values were large for both the MRI-SUV and MRI-TBR combinations because the regions of PET uptake were generally larger than the MRI enhancement. Notable differences in the tumor dose volume histograms were observed for each patient. The mean (standard deviation) 131I-CLR1404 tumor doses ranged from 0.28-1.75 Gy GBq-1 (0.07-0.37 Gy GBq-1). The ratio of maximum-to-minimum mean doses for each patient ranged from 1.4-2.0. The tumor volume and the interpretation of the tumor dose is highly sensitive to the imaging modality, PET enhancement metric, and threshold level used for tumor volume segmentation. The large variations in tumor doses clearly demonstrate the need for standard

  18. Stable transport in proton driven fast ignition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bret, A.

    2009-09-15

    Proton beam transport in the context of proton driven fast ignition is usually assumed to be stable due to proton high inertia, but an analytical analysis of the process is still lacking. The stability of a charge and current neutralized proton beam passing through a plasma is therefore conducted here, for typical proton driven fast ignition parameters. In the cold regime, two fast growing modes are found, with an inverse growth rate much smaller than the beam time of flight to the target core. The stability issue is thus not so obvious, and kinetic effects are investigated. One unstable modemore » is found stabilized by the background plasma proton and electron temperatures. The second mode is also damped, providing the proton beam thermal spread is larger than {approx}10 keV. In fusion conditions, the beam propagation should therefore be stable.« less

  19. A toy story: Association between young children's knowledge of fast food toy premiums and their fast food consumption.

    PubMed

    Longacre, Meghan R; Drake, Keith M; Titus, Linda J; Cleveland, Lauren P; Langeloh, Gail; Hendricks, Kristy; Dalton, Madeline A

    2016-01-01

    Fast food restaurants spend millions of dollars annually on child-targeted marketing, a substantial portion of which is allocated to toy premiums for kids' meals. The objectives of this study were to describe fast food toy premiums, and examine whether young children's knowledge of fast food toy premiums was associated with their fast food consumption. Parents of 3- to 5-year old children were recruited from pediatric and WIC clinics in Southern New Hampshire, and completed a cross-sectional survey between April 2013-March 2014. Parents reported whether their children usually knew what toys were being offered at fast food restaurants, and whether children had eaten at any of four restaurants that offer toy premiums with kids' meals (McDonald's, Burger King, Subway, Wendy's) during the 7 days preceding the survey. Seventy-one percent of eligible parents participated (N = 583); 48.4% did not receive any education beyond high school, and 27.1% of children were non-white. Half (49.7%) the children had eaten at one or more of the four fast food restaurants in the past week; one-third (33.9%) had eaten at McDonald's. The four restaurants released 49 unique toy premiums during the survey period; McDonald's released half of these. Even after controlling for parent fast food consumption and sociodemographics, children were 1.38 (95% CI = 1.04, 1.82) times more likely to have consumed McDonald's if they usually knew what toys were offered by fast food restaurants. We did not detect a relationship between children's toy knowledge and their intake of fast food from the other restaurants. In this community-based sample, young children's knowledge of fast food toys was associated with a greater frequency of eating at McDonald's, providing evidence in support of regulating child-directed marketing of unhealthy foods using toys. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Maxillary sinus volume in patients with impacted canines.

    PubMed

    Oz, Aslihan Zeynep; Oz, Abdullah Alper; El, Hakan; Palomo, Juan Martin

    2017-01-01

    To evaluate the maxillary sinus volumes in unilaterally impacted canine patients and to compare the volumetric changes that occur after the eruption of canines to the dental arch using cone beam computed tomography (CBCT). Pre- (T0) and posttreatment (T1) CBCT records of 30 patients were used to calculate maxillary sinus volumes between the impacted and erupted canine sides. The InVivoDental 5.0 program was used to measure the volume of the maxillary sinuses. The distance from impacted canine cusp tip to the target point on the palatal plane was also measured. Right maxillary sinus volume was statistically significantly smaller compared to that of the left maxillary sinus when the canine was impacted on the right side at T0. According to the T1 measurements there was no significant difference between the mean volumes of the impaction side and the contralateral side. The distance from the canine tip to its target point on the palatal plane were 17.17 mm, and the distance from the tip to the target point was 15.14 mm for the left- and right-side impacted canines, respectively, and there was a significant difference between the mean amount of change of both sides of maxillary sinuses after treatment of impacted canines. Orthodontic treatment of impacted canines created a significant increase in maxillary sinus volume when the impacted canines were closer with respect to the maxillary sinus.

  1. Nuclear reactor target assemblies, nuclear reactor configurations, and methods for producing isotopes, modifying materials within target material, and/or characterizing material within a target material

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Toth, James J.; Wall, Donald; Wittman, Richard S.

    Target assemblies are provided that can include a uranium-comprising annulus. The assemblies can include target material consisting essentially of non-uranium material within the volume of the annulus. Reactors are disclosed that can include one or more discrete zones configured to receive target material. At least one uranium-comprising annulus can be within one or more of the zones. Methods for producing isotopes within target material are also disclosed, with the methods including providing neutrons to target material within a uranium-comprising annulus. Methods for modifying materials within target material are disclosed as well as are methods for characterizing material within a targetmore » material.« less

  2. Effect of Ramadan fasting on urinary risk factors for calculus formation.

    PubMed

    Miladipour, Amir Hossein; Shakhssalim, Nasser; Parvin, Mahmoud; Azadvari, Mohaddeseh

    2012-01-01

    Even though dehydration could aggravate formation of urinary calculi, the effects of fluid and food restriction on calculus formation is not thoroughly defined. The purpose of this study is to evaluate the effects of fluid and food restriction in Ramadan fasting on urinary factors in kidney and urinary calculus formation. Fifty-seven men aged 30 to 55 years old, including 37 recurrent calcium calculus formers and 20 with no history of kidney calculi were evaluated for blood tests, ultrasonography investigations, urinalysis, urine culture, and also 24-hour urine collection test. Metabolites including calcium, oxalate, citrate, uric acid, magnesium, phosphate, potassium, sodium, and creatinine were measured before and during Ramadan fasting. The values of calculus-precipitating solutes as well as inhibitory factors were documented thoroughly. Total excretion of calcium, phosphate, and magnesium in 24-hour urine and also urine volume during fasting were significantly lower than those in the nonfasting period. Urine concentration of calcium during fasting was significantly lower than nonfasting (P < .001). Urine concentrations of uric acid, citrate, phosphate, sodium, and potassium during fasting were significantly higher than nonfasting. Uric acid supersaturation was accentuated, and calcium phosphate supersaturation was decreased significantly during fasting. There was no significant increase in calcium oxalate supersaturation during the fasting period. Fasting during Ramadan has different effects on total excretion and concentrations of urinary precipitate and inhibitory factors contributing to calculus formation. We did not find enough evidence in favor of increased risks of calculus formation during Ramadan fasting.

  3. Setup Variations in Radiotherapy of Anal Cancer: Advantages of Target Volume Reduction Using Image-Guided Radiation Treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen Yijen, E-mail: yichen@coh.org; Suh, Steve; Nelson, Rebecca A.

    2012-09-01

    Purpose: To define setup variations in the radiation treatment (RT) of anal cancer and to report the advantages of image-guided RT (IGRT) in terms of reduction of target volume and treatment-related side effects. Methods and Materials: Twelve consecutive patients with anal cancer treated by combined chemoradiation by use of helical tomotherapy from March 2007 to November 2008 were selected. With patients immobilized and positioned in place, megavoltage computed tomography (MVCT) scans were performed before each treatment and were automatically registered to planning CT scans. Patients were shifted per the registration data and treated. A total of 365 MVCT scans weremore » analyzed. The primary site received a median dose of 55 Gy. To evaluate the potential dosimetric advantage(s) of IGRT, cases were replanned according to Radiation Therapy Oncology Group 0529, with and without adding recommended setup variations from the current study. Results: Significant setup variations were observed throughout the course of RT. The standard deviations for systematic setup correction in the anterior-posterior (AP), lateral, and superior-inferior (SI) directions and roll rotation were 1.1, 3.6, and 3.2 mm, and 0.3 Degree-Sign , respectively. The average random setup variations were 3.8, 5.5, and 2.9 mm, and 0.5 Degree-Sign , respectively. Without daily IGRT, margins of 4.9, 11.1, and 8.5 mm in the AP, lateral, and SI directions would have been needed to ensure that the planning target volume (PTV) received {>=}95% of the prescribed dose. Conversely, daily IGRT required no extra margins on PTV and resulted in a significant reduction of V15 and V45 of intestine and V10 of pelvic bone marrow. Favorable toxicities were observed, except for acute hematologic toxicity. Conclusions: Daily MVCT scans before each treatment can effectively detect setup variations and thereby reduce PTV margins in the treatment of anal cancer. The use of concurrent chemotherapy and IGRT provided favorable

  4. Distance-to-Agreement Investigation of Tomotherapy's Bony Anatomy-Based Autoregistration and Planning Target Volume Contour-Based Optimization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Suh, Steve, E-mail: ssuh@coh.org; Schultheiss, Timothy E.

    Purpose: To compare Tomotherapy's megavoltage computed tomography bony anatomy autoregistration with the best achievable registration, assuming no deformation and perfect knowledge of planning target volume (PTV) location. Methods and Materials: Distance-to-agreement (DTA) of the PTV was determined by applying a rigid-body shift to the PTV region of interest of the prostate from its reference position, assuming no deformations. Planning target volume region of interest of the prostate was extracted from the patient archives. The reference position was set by the 6 degrees of freedom (dof)—x, y, z, roll, pitch, and yaw—optimization results from the previous study at this institution. Themore » DTA and the compensating parameters were calculated by the shift of the PTV from the reference 6-dof to the 4-dof—x, y, z, and roll—optimization. In this study, the effectiveness of Tomotherapy's 4-dof bony anatomy–based autoregistration was compared with the idealized 4-dof PTV contour-based optimization. Results: The maximum DTA (maxDTA) of the bony anatomy-based autoregistration was 3.2 ± 1.9 mm, with the maximum value of 8.0 mm. The maxDTA of the contour-based optimization was 1.8 ± 1.3 mm, with the maximum value of 5.7 mm. Comparison of Pearson correlation of the compensating parameters between the 2 4-dof optimization algorithms shows that there is a small but statistically significant correlation in y and z (0.236 and 0.300, respectively), whereas there is very weak correlation in x and roll (0.062 and 0.025, respectively). Conclusions: We find that there is an average improvement of approximately 1 mm in terms of maxDTA on the PTV going from 4-dof bony anatomy-based autoregistration to the 4-dof contour-based optimization. Pearson correlation analysis of the 2 4-dof optimizations suggests that uncertainties due to deformation and inadequate resolution account for much of the compensating parameters, but pitch variation also makes a statistically

  5. Renal responses to plasma volume expansion and hyperosmolality in fasting seal pups

    NASA Technical Reports Server (NTRS)

    Ortiz, Rudy M.; Wade, Charles E.; Costa, Daniel P.; Ortiz, C. Leo

    2002-01-01

    Renal responses were quantified in northern elephant seal (Mirounga angustirostris) pups during their postweaning fast to examine their excretory capabilities. Pups were infused with either isotonic (0.9%; n = 8; Iso) or hypertonic (16.7%; n = 7; Hyper) saline via an indwelling catheter such that each pup received 3 mmol NaCl/kg. Diuresis after the infusions was similar in magnitude between the two treatments. Osmotic clearance increased by 37% in Iso and 252% in Hyper. Free water clearance was reduced 3.4-fold in Hyper but was not significantly altered in Iso. Glomerular filtration rate increased 71% in the 24-h period after Hyper, but no net change occurred during the same time after Iso. Natriuresis increased 3.6-fold in Iso and 5.3-fold in Hyper. Iso decreased plasma arginine vasopressin (AVP) and cortisol acutely, whereas Hyper increased plasma and excreted AVP and cortisol. Iso was accompanied by the retention of water and electrolytes, whereas the Hyper load was excreted within 24 h. Natriuresis is attributed to increased filtration and is independent of an increase in atrial natriuretic peptide and decreases in ANG II and aldosterone. Fasting pups appear to have well-developed kidneys capable of both extreme conservation and excretion of Na(+).

  6. Risk of misclassification with a non-fasting lipid profile in secondary cardiovascular prevention.

    PubMed

    Klop, Boudewijn; Hartong, Simone C C; Vermeer, Henricus J; Schoofs, Mariette W C J; Kofflard, Marcel J M

    2017-09-01

    Routinely fasting is not necessary for measuring the lipid profile according to the latest European consensus. However, LDL-C tends to be lower in the non-fasting state with risk of misclassification. The extent of misclassification in secondary cardiovascular prevention with a non-fasting lipid profile was investigated. 329 patients on lipid lowering therapy for secondary cardiovascular prevention measured a fasting and non-fasting lipid profile. Cut-off values for LDL-C, non-HDL-C and apolipoprotein B were set at <1.8mmol/l, <2.6mmol/l and <0.8g/l, respectively. Study outcomes were net misclassification with non-fasting LDL-C (calculated using the Friedewald formula), direct LDL-C, non-HDL-C and apolipoprotein B. Net misclassification <10% was considered clinically irrelevant. Mean age was 68.3±8.5years and the majority were men (79%). Non-fasting measurements resulted in lower LDL-C (-0.2±0.4mmol/l, P<0.001), direct LDL-C (-0.1±0.2mmol/l, P=0.001), non-HDL-C (-0.1±0.4mmol/l, P=0.004) and apolipoprotein B (-0.02±0.10g/l, P=0.004). 36.0% of the patients reached a fasting LDL-C target of <1.8mmol/l with a significant net misclassification of 10.7% (95% CI 6.4-15.0%) in the non-fasting state. In the non-fasting state net misclassification with direct LDL-C was 5.7% (95% CI 2.1-9.2%), 4.0% (95% CI 1.0-7.4%) with non-HDL-C and 4.1% (95% CI 1.1-9.1%) with apolipoprotein B. Use of non-fasting LDL-C as treatment target in secondary cardiovascular prevention resulted in significant misclassification with subsequent risk of undertreatment, whereas non-fasting direct LDL-C, non-HDL-C and apolipoprotein B are reliable parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Is Fasting for Ramadan Safe in Patients with Mechanical Cardiac Valves?

    PubMed

    Yildirim, Ersin; Secen, Ozlem; Uku, Okkes; Nail Bilen, Mehmet; Kutlu Karadag, Makbule

    2017-03-01

    The study aim was to investigate the safety and effects of fasting during Ramadan on the International Normalized Ratio (INR) in patients with mechanical cardiac valves. A total of 105 patients admitted to the authors' hospital between June and October 2015, who had history of prosthetic valve replacement, was investigated. The patients were allocated to two groups: those fasting during Ramadan (n = 42) and those not fasting (n = 63). All patients were examined by a cardiologist, and the clinical findings and complaints for the past three months were evaluated. The INR, complete blood count (CBC) and a basic biochemical panel were monitored for all patients. The mean corpuscular volume (MCV) of the fasting group was significantly higher than that of the non- fasting group (87.59 ± 6.39 (μm3) versus 84.28 ± 6.387 (μm3); p = 0.011). Other CBC parameters and basic biochemical values did not differ significantly different between groups. Neither were significant differences noted in INR values during Ramadan (fasting group 2.87 ± 0.97; non-fasting group 2.73 ± 0.78; p = 0.50) and at routine control one month later (fasting group 3.07 ± 1.55; non-fasting group 2.94 ± 1.03; p = 0.601). No significant differences related to increased rates of hospitalization, valvular dysfunction on echocardiography, thrombus, embolism, bleeding and clinical complaints were identified between the groups. Fasting during Ramadan had no adverse effects on the INR of patients, and appears to be safe for patients with mechanical prosthetic cardiac valves.

  8. Are We Ready for Positron Emission Tomography/Computed Tomography-based Target Volume Definition in Lymphoma Radiation Therapy?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yeoh, Kheng-Wei; Mikhaeel, N. George, E-mail: George.Mikhaeel@gstt.nhs.uk

    2013-01-01

    Fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) has become indispensable for the clinical management of lymphomas. With consistent evidence that it is more accurate than anatomic imaging in the staging and response assessment of many lymphoma subtypes, its utility continues to increase. There have therefore been efforts to incorporate PET/CT data into radiation therapy decision making and in the planning process. Further, there have also been studies investigating target volume definition for radiation therapy using PET/CT data. This article will critically review the literature and ongoing studies on the above topics, examining the value and methods of adding PET/CTmore » data to the radiation therapy treatment algorithm. We will also discuss the various challenges and the areas where more evidence is required.« less

  9. Fast Coherent Differential Imaging for Exoplanet Imaging

    NASA Astrophysics Data System (ADS)

    Gerard, Benjamin; Marois, Christian; Galicher, Raphael; Veran, Jean-Pierre; Macintosh, B.; Guyon, O.; Lozi, J.; Pathak, P.; Sahoo, A.

    2018-06-01

    Direct detection and detailed characterization of exoplanets using extreme adaptive optics (ExAO) is a key science goal of future extremely large telescopes and space observatories. However, quasi-static wavefront errors will limit the sensitivity of this endeavor. Additional limitations for ground-based telescopes arise from residual AO-corrected atmospheric wavefront errors, generating short-lived aberrations that will average into a halo over a long exposure, also limiting the sensitivity of exoplanet detection. We develop the framework for a solution to both of these problems using the self-coherent camera (SCC), to be applied to ground-based telescopes, called Fast Atmospheric SCC Technique (FAST). Simulations show that for typical ExAO targets the FAST approach can reach ~100 times better in raw contrast than what is currently achieved with ExAO instruments if we extrapolate for an hour of observing time, illustrating that the sensitivity improvement from this method could play an essential role in the future ground-based detection and characterization of lower mass/colder exoplanets.

  10. Conceptual design of laser fusion reactor KOYO-fast Concepts of reactor system and laser driver

    NASA Astrophysics Data System (ADS)

    Kozaki, Y.; Miyanaga, N.; Norimatsu, T.; Soman, Y.; Hayashi, T.; Furukawa, H.; Nakatsuka, M.; Yoshida, K.; Nakano, H.; Kubomura, H.; Kawashima, T.; Nishimae, J.; Suzuki, Y.; Tsuchiya, N.; Kanabe, T.; Jitsuno, T.; Fujita, H.; Kawanaka, J.; Tsubakimoto, K.; Fujimoto, Y.; Lu, J.; Matsuoka, S.; Ikegawa, T.; Owadano, Y.; Ueda, K.; Tomabechi, K.; Reactor Design Committee in Ife Forum, Members Of

    2006-06-01

    We have carried out the design studies of KOYO-Fast laser fusion power plant, using fast ignition cone targets, DPSSL lasers, and LiPb liquid wall chambers. Using fast ignition targets, we could design a middle sized 300 MWe reactor module, with 200 MJ fusion pulse energy and 4 Hz rep-rates, and 1200MWe modular power plants with 4 reactor modules and a 16 Hz laser driver. The liquid wall chambers with free surface cascade flows are proposed for cooling surface quickly enough to a 4 Hz pulse operation. We examined the potential of Yb-YAG ceramic lasers operated at 150˜ 225 K for both implosion and heating laser systems required for a 16-Hz repetition and 8 % total efficiency.

  11. A Toy Story: Association between Young Children’s Knowledge of Fast Food Toy Premiums and their Fast Food Consumption

    PubMed Central

    Longacre, Meghan R.; Drake, Keith M.; Titus, Linda J.; Cleveland, Lauren P.; Langeloh, Gail; Hendricks, Kristy; Dalton, Madeline A.

    2015-01-01

    Fast food restaurants spend millions of dollars annually on child-targeted marketing, a substantial portion of which is allocated to toy premiums for kids’ meals. The objectives of this study were to describe fast food toy premiums, and examine whether young children’s knowledge of fast food toy premiums was associated with their fast food consumption. Parents of 3- to 5-year old children were recruited from pediatric and WIC clinics in Southern New Hampshire, and completed a cross-sectional survey between April 2013–March 2014. Parents reported whether their children usually knew what toys were being offered at fast food restaurants, and whether children had eaten at any of four restaurants that offer toy premiums with kids’ meals (McDonald’s, Burger King, Subway, Wendy’s) during the 7 days preceding the survey. Seventy-one percent of eligible parents participated (N=583); 48.4% did not receive any education beyond high school, and 27.1% of children were non-white. Half (49.7%) the children had eaten at one or more of the four fast food restaurants in the past week; one-third (33.9%) had eaten at McDonald’s. The four restaurants released 49 unique toy premiums during the survey period; McDonald’s released half of these. Even after controlling for parent fast food consumption and sociodemographics, children were 1.38 (95% CI=1.04, 1.82) times more likely to have consumed McDonald’s if they usually knew what toys were offered by fast food restaurants. We did not detect a relationship between children’s toy knowledge and their intake of fast food from the other restaurants. In this community-based sample, young children’s knowledge of fast food toys was associated with a greater frequency of eating at McDonald’s, providing evidence in support of regulating child-directed marketing of unhealthy foods using toys. PMID:26471803

  12. Collective Thomson scattering measurements of fast-ion transport due to sawtooth crashes in ASDEX Upgrade

    NASA Astrophysics Data System (ADS)

    Rasmussen, J.; Nielsen, S. K.; Stejner, M.; Galdon-Quiroga, J.; Garcia-Munoz, M.; Geiger, B.; Jacobsen, A. S.; Jaulmes, F.; Korsholm, S. B.; Lazanyi, N.; Leipold, F.; Ryter, F.; Salewski, M.; Schubert, M.; Stober, J.; Wagner, D.; the ASDEX Upgrade Team; the EUROFusion MST1 Team

    2016-11-01

    Sawtooth instabilities can modify heating and current-drive profiles and potentially increase fast-ion losses. Understanding how sawteeth redistribute fast ions as a function of sawtooth parameters and of fast-ion energy and pitch is hence a subject of particular interest for future fusion devices. Here we present the first collective Thomson scattering (CTS) measurements of sawtooth-induced redistribution of fast ions at ASDEX Upgrade. These also represent the first localized fast-ion measurements on the high-field side of this device. The results indicate fast-ion losses in the phase-space measurement volume of about 50% across sawtooth crashes, in good agreement with values predicted with the Kadomtsev sawtooth model implemented in TRANSP and with the sawtooth model in the EBdyna_go code. In contrast to the case of sawteeth, we observe no fast-ion redistribution in the presence of fishbone modes. We highlight how CTS measurements can discriminate between different sawtooth models, in particular when aided by multi-diagnostic velocity-space tomography, and briefly discuss our results in light of existing measurements from other fast-ion diagnostics.

  13. New approach to the fast screening of plant oil samples for F-, Cl-, Br- and S-organic compounds on the trace level.

    PubMed

    Chivarzin, M E; Revelsky, I A; Nikoshina, A V; Buldyzkova, A N; Chepeliansky, D A; Revelsky, A I; Buriak, A K

    2016-04-01

    The fast method of the simultaneous determination of F(-), Cl(-), Br(-) and SO4(2-) anions in the deionized water on the trace level by ion chromatography using thorough cleaning of respective water containers, 10 μM NaHCO3 water solution as eluent, short Metrohm (50 × 4 mm) separation column and a large water volume injection is proposed. Calculated detection limits are 10(-9)-10(-8)% depending on the element. The method for the fast screening of plant oil samples for the total fluorine-, chlorine-, bromine- and sulfur-organic compounds content (calculated for the respective elements) on the trace level is developed. It is based on the high temperature combustion of oil sample in oxygen flow, absorption of the conversion products in deionized water and whole absorbate volume analysis for F(-), Cl(-), Br(-) and SO4(2-) anions, corresponding to the respective elements, using the developed method of these anions analysis by ion chromatography. The samples of soya, olive, sunflower and cotton seed oil were analyzed. The method detection limits (for 1mg sample) were 2 × 10(-6)%, 2 × 10(-6)%, 5 × 10(-6)% and 5 × 10(-6)% for fluorine, chlorine, bromine and sulfur, respectively. The relative standard deviation was ≤ 15%. The method gives the compressed information about the total content of all target and nontarget fluorine-, chlorine-, bromine- and sulfur-organic compounds in plant oils. Copyright © 2015. Published by Elsevier B.V.

  14. Planned Subtotal Resection of Vestibular Schwannoma Differs from the Ideal Radiosurgical Target Defined by Adaptive Hybrid Surgery.

    PubMed

    Sheppard, John P; Lagman, Carlito; Prashant, Giyarpuram N; Alkhalid, Yasmine; Nguyen, Thien; Duong, Courtney; Udawatta, Methma; Gaonkar, Bilwaj; Tenn, Stephen E; Bloch, Orin; Yang, Isaac

    2018-06-01

    To retrospectively compare ideal radiosurgical target volumes defined by a manual method (surgeon) to those determined by Adaptive Hybrid Surgery (AHS) operative planning software in 7 patients with vestibular schwannoma (VS). Four attending surgeons (3 neurosurgeons and 1 ear, nose, and throat surgeon) manually contoured planned residual tumors volumes for 7 consecutive patients with VS. Next, the AHS software determined the ideal radiosurgical target volumes based on a specified radiotherapy plan. Our primary measure was the difference between the average planned residual tumor volumes and the ideal radiosurgical target volumes defined by AHS (dRV AHS-planned ). We included 7 consecutive patients with VS in this study. The planned residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (1.6 vs. 4.5 cm 3 , P = 0.004). On average, the actual post-operative residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (2.2 cm 3 vs. 4.5 cm 3 ; P = 0.02). The average difference between the ideal radiosurgical target volume defined by AHS and the planned residual tumor volume (dRV AHS-planned ) was 2.9 ± 1.7 cm 3 , and we observed a trend toward larger dRV AHS-planned in patients who lost serviceable facial nerve function compared with patients who maintained serviceable facial nerve function (4.7 cm 3 vs. 1.9 cm 3 ; P = 0.06). Planned subtotal resection of VS diverges from the ideal radiosurgical target defined by AHS, but whether that influences clinical outcomes is unclear. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Detection and volume estimation of embolic air in the middle cerebral artery using transcranial Doppler sonography.

    PubMed

    Bunegin, L; Wahl, D; Albin, M S

    1994-03-01

    Cerebral embolism has been implicated in the development of cognitive and neurological deficits following bypass surgery. This study proposes methodology for estimating cerebral air embolus volume using transcranial Doppler sonography. Transcranial Doppler audio signals of air bubbles in the middle cerebral artery obtained from in vivo experiments were subjected to a fast-Fourier transform analysis. Audio segments when no air was present as well as artifact resulting from electrocautery and sensor movement were also subjected to fast-Fourier transform analysis. Spectra were compared, and frequency and power differences were noted and used for development of audio band-pass filters for isolation of frequencies associated with air emboli. In a bench model of the middle cerebral artery circulation, repetitive injections of various air volumes between 0.5 and 500 microL were made. Transcranial Doppler audio output was band-pass filtered, acquired digitally, then subjected to a fast-Fourier transform power spectrum analysis and power spectrum integration. A linear least-squares correlation was performed on the data. Fast-Fourier transform analysis of audio segments indicated that frequencies between 250 and 500 Hz are consistently dominant in the spectrum when air emboli are present. Background frequencies appear to be below 240 Hz, and artifact resulting from sensor movement and electrocautery appears to be below 300 Hz. Data from the middle cerebral artery model filtered through a 307- to 450-Hz band-pass filter yielded a linear relation between emboli volume and the integrated value of the power spectrum near 40 microL. Detection of emboli less than 0.5 microL was inconsistent, and embolus volumes greater than 40 microL were indistinguishable from one another. The preliminary technique described in this study may represent a starting point from which automated detection and volume estimation of cerebral emboli might be approached.

  16. Neighborhood fast food availability and fast food consumption.

    PubMed

    Oexle, Nathalie; Barnes, Timothy L; Blake, Christine E; Bell, Bethany A; Liese, Angela D

    2015-09-01

    Recent nutritional and public health research has focused on how the availability of various types of food in a person's immediate area or neighborhood influences his or her food choices and eating habits. It has been theorized that people living in areas with a wealth of unhealthy fast-food options may show higher levels of fast-food consumption, a factor that often coincides with being overweight or obese. However, measuring food availability in a particular area is difficult to achieve consistently: there may be differences in the strict physical locations of food options as compared to how individuals perceive their personal food availability, and various studies may use either one or both of these measures. The aim of this study was to evaluate the association between weekly fast-food consumption and both a person's perceived availability of fast-food and an objective measure of fast-food presence - Geographic Information Systems (GIS) - within that person's neighborhood. A randomly selected population-based sample of eight counties in South Carolina was used to conduct a cross-sectional telephone survey assessing self-report fast-food consumption and perceived availability of fast food. GIS was used to determine the actual number of fast-food outlets within each participant's neighborhood. Using multinomial logistic regression analyses, we found that neither perceived availability nor GIS-based presence of fast-food was significantly associated with weekly fast-food consumption. Our findings indicate that availability might not be the dominant factor influencing fast-food consumption. We recommend using subjective availability measures and considering individual characteristics that could influence both perceived availability of fast food and its impact on fast-food consumption. If replicated, our findings suggest that interventions aimed at reducing fast-food consumption by limiting neighborhood fast-food availability might not be completely effective

  17. Intra-tumour 18F-FDG uptake heterogeneity decreases the reliability on target volume definition with positron emission tomography/computed tomography imaging.

    PubMed

    Dong, Xinzhe; Wu, Peipei; Sun, Xiaorong; Li, Wenwu; Wan, Honglin; Yu, Jinming; Xing, Ligang

    2015-06-01

    This study aims to explore whether the intra-tumour (18) F-fluorodeoxyglucose (FDG) uptake heterogeneity affects the reliability of target volume definition with FDG positron emission tomography/computed tomography (PET/CT) imaging for nonsmall cell lung cancer (NSCLC) and squamous cell oesophageal cancer (SCEC). Patients with NSCLC (n = 50) or SCEC (n = 50) who received (18)F-FDG PET/CT scanning before treatments were included in this retrospective study. Intra-tumour FDG uptake heterogeneity was assessed by visual scoring, the coefficient of variation (COV) of the standardised uptake value (SUV) and the image texture feature (entropy). Tumour volumes (gross tumour volume (GTV)) were delineated on the CT images (GTV(CT)), the fused PET/CT images (GTV(PET-CT)) and the PET images, using a threshold at 40% SUV(max) (GTV(PET40%)) or the SUV cut-off value of 2.5 (GTV(PET2.5)). The correlation between the FDG uptake heterogeneity parameters and the differences in tumour volumes among GTV(CT), GTV(PET-CT), GTV(PET40%) and GTV(PET2.5) was analysed. For both NSCLC and SCEC, obvious correlations were found between uptake heterogeneity, SUV or tumour volumes. Three types of heterogeneity parameters were consistent and closely related to each other. Substantial differences between the four methods of GTV definition were found. The differences between the GTV correlated significantly with PET heterogeneity defined with the visual score, the COV or the textural feature-entropy for NSCLC and SCEC. In tumours with a high FDG uptake heterogeneity, a larger GTV delineation difference was found. Advance image segmentation algorithms dealing with tracer uptake heterogeneity should be incorporated into the treatment planning system. © 2015 The Royal Australian and New Zealand College of Radiologists.

  18. Fast-match on particle swarm optimization with variant system mechanism

    NASA Astrophysics Data System (ADS)

    Wang, Yuehuang; Fang, Xin; Chen, Jie

    2018-03-01

    Fast-Match is a fast and effective algorithm for approximate template matching under 2D affine transformations, which can match the target with maximum similarity without knowing the target gesture. It depends on the minimum Sum-of-Absolute-Differences (SAD) error to obtain the best affine transformation. The algorithm is widely used in the field of matching images because of its fastness and robustness. In this paper, our approach is to search an approximate affine transformation over Particle Swarm Optimization (PSO) algorithm. We treat each potential transformation as a particle that possesses memory function. Each particle is given a random speed and flows throughout the 2D affine transformation space. To accelerate the algorithm and improve the abilities of seeking the global excellent result, we have introduced the variant system mechanism on this basis. The benefit is that we can avoid matching with huge amount of potential transformations and falling into local optimal condition, so that we can use a few transformations to approximate the optimal solution. The experimental results prove that our method has a faster speed and a higher accuracy performance with smaller affine transformation space.

  19. Application of single-shot spiral scanning for volume localization.

    PubMed

    Ra, J B; Rim, C Y; Cho, Z H

    1991-02-01

    A new technique using a spiral scan single-shot RF pulse for localized volume selection has been developed and its experimental results are presented. This technique employs an additional radial-gradient coil in conjunction with the oscillating gradients for the spiral scan to localize the 3D volume. The short selection time in this technique minimizes both signal contamination from unwanted regions and signal attenuation due to T2 decay. We provide both the theoretical background of the technique and the experimental results obtained from a phantom as well as a human volunteer. The proposed method appears simple and accurate in localizing a volume which would be used as either fast imaging or localized spectroscopy.

  20. A novel guidance law using fast terminal sliding mode control with impact angle constraints.

    PubMed

    Sun, Lianghua; Wang, Weihong; Yi, Ran; Xiong, Shaofeng

    2016-09-01

    This paper is concerned with the question of, for a missile interception with impact angle constraints, how to design a guidance law. Firstly, missile interception with impact angle constraints is modeled; secondly, a novel guidance law using fast terminal sliding mode control based on extended state observer is proposed to optimize the trajectory and time of interception; finally, for stationary targets, constant velocity targets and maneuvering targets, the guidance law and the stability of the closed loop system is analyzed and the stability of the closed loop system is analyzed, respectively. Simulation results show that when missile and target are on a collision course, the novel guidance law using fast terminal sliding mode control with extended state observer has more optimized trajectory and effectively reduces the time of interception which has a great significance in modern warfare. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Comprehensive approach to fast ion measurements in the beam-driven FRC

    NASA Astrophysics Data System (ADS)

    Magee, Richard; Smirnov, Artem; Onofri, Marco; Dettrick, Sean; Korepanov, Sergey; Knapp, Kurt; the TAE Team

    2015-11-01

    The C-2U experiment combines tangential neutral beam injection, edge biasing, and advanced recycling control to explore the sustainment of field-reversed configuration (FRC) plasmas. To study fast ion confinement in such advanced, beam-driven FRCs, a synergetic technique was developed that relies on the measurements of the DD fusion reaction products and the hybrid code Q2D, which treats the plasma as a fluid and the fast ions kinetically. Data from calibrated neutron and proton detectors are used in a complementary fashion to constrain the simulations: neutron detectors measure the volume integrated fusion rate to constrain the total number of fast ions, while proton detectors with multiple lines of sight through the plasma constrain the axial profile of fast ions. One application of this technique is the diagnosis of fast ion energy transfer and pitch angle scattering. A parametric numerical study was conducted, in which additional ad hoc loss and scattering terms of varying strengths were introduced in the code and constrained with measurement. Initial results indicate that the energy transfer is predominantly classical, while, in some cases, non-classical pitch angle scattering can be observed.

  2. Fast, Computer Supported Experimental Determination of Absolute Zero Temperature at School

    ERIC Educational Resources Information Center

    Bogacz, Bogdan F.; Pedziwiatr, Antoni T.

    2014-01-01

    A simple and fast experimental method of determining absolute zero temperature is presented. Air gas thermometer coupled with pressure sensor and data acquisition system COACH is applied in a wide range of temperature. By constructing a pressure vs temperature plot for air under constant volume it is possible to obtain--by extrapolation to zero…

  3. Determination of Internal Target Volume for Radiation Treatment Planning of Esophageal Cancer by Using 4-Dimensional Computed Tomography (4DCT)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Xiaojian; Lu, Haijun; Radiation Oncology Center, Affiliated Hospital of Medical College, Qingdao University, Qingdao

    2014-09-01

    Purpose: To determine an efficient strategy for the generation of the internal target volume (ITV) for radiation treatment planning for esophageal cancer using 4-dimensional computed tomography (4DCT). Methods and Materials: 4DCT sets acquired for 20 patients with esophageal carcinoma were analyzed. Each of the 4DCT sets was binned into 10 respiratory phases. For each patient, the gross tumor volume (GTV) was delineated on the 4DCT set at each phase. Various strategies to derive ITV were explored, including the volume from the maximum intensity projection (MIP; ITV{sub M}IP), unions of the GTVs from selected multiple phases ITV2 (0% and 50% phases), ITV3 (ITV2more » plus 80%), and ITV4 (ITV3 plus 60%), as well as the volumes expanded from ITV2 and ITV3 with a uniform margin. These ITVs were compared to ITV10 (the union of the GTVs for all 10 phases) and the differences were measured with the overlap ratio (OR) and relative volume ratio (RVR) relative to ITV10 (ITVx/ITV10). Results: For all patients studied, the average GTV from a single phase was 84.9% of ITV10. The average ORs were 91.2%, 91.3%, 94.5%, and 96.4% for ITV{sub M}IP, ITV2, ITV3, and ITV4, respectively. Low ORs were associated with irregular breathing patterns. ITV3s plus 1 mm uniform margins (ITV3+1) led to an average OR of 98.1% and an average RVR of 106.4%. Conclusions: The ITV generated directly from MIP underestimates the range of the respiration motion for esophageal cancer. The ITV generated from 3 phases (ITV3) may be used for regular breathers, whereas the ITV generated from 4 phases (ITV4) or ITV3 plus a 1-mm uniform margin may be applied for irregular breathers.« less

  4. Intensity modulated radiation therapy (IMRT): differences in target volumes and improvement in clinically relevant doses to small bowel in rectal carcinoma.

    PubMed

    Mok, Henry; Crane, Christopher H; Palmer, Matthew B; Briere, Tina M; Beddar, Sam; Delclos, Marc E; Krishnan, Sunil; Das, Prajnan

    2011-06-08

    , without incurring penalty with respect to adjacent organs-at-risk. For rectal carcinoma, IMRT, compared to 3DCRT, yielded plans superior with respect to target coverage, homogeneity, and conformality, while lowering dose to adjacent organs-at-risk. This is achieved despite treating larger volumes, raising the possibility of a clinically-relevant improvement in the therapeutic ratio through the use of IMRT with a belly-board apparatus.

  5. Bioavailability of Tetracycline and Doxycycline in Fasted and Nonfasted Subjects

    PubMed Central

    Welling, Peter G.; Koch, Patricia A.; Lau, Curtis C.; Craig, William A.

    1977-01-01

    The influence of various test meals and fluid volumes on the relative bioavailability of commercial formulations of doxycycline hyclate and tetracycline hydrochloride was studied in healthy human volunteers. Serum levels of tetracycline were uniformly reduced by approximately 50% by all test meals, whereas serum levels of doxycycline were reduced by 20%. The reduction of tetracycline serum levels will likely be of clinical significance. The bioavailability of each drug was almost identical from an oral solution and from capsules in fasted subjects. The rate of doxycycline absorption was reduced when capsules were administered with a small volume of water, but the overall efficiency of absorption of both drugs was essentially independent of co-administered fluid volume. The use of 8-h serum data provides a reliable estimate of drug bioavailability for tetracycline and, to a lesser extent, for doxycycline. PMID:856000

  6. Activity targets for nanostructured platinum-group-metal-free catalysts in hydroxide exchange membrane fuel cells.

    PubMed

    Setzler, Brian P; Zhuang, Zhongbin; Wittkopf, Jarrid A; Yan, Yushan

    2016-12-06

    Fuel cells are the zero-emission automotive power source that best preserves the advantages of gasoline automobiles: low upfront cost, long driving range and fast refuelling. To make fuel-cell cars a reality, the US Department of Energy has set a fuel cell system cost target of US$30 kW -1 in the long-term, which equates to US$2,400 per vehicle, excluding several major powertrain components (in comparison, a basic, but complete, internal combustion engine system costs approximately US$3,000). To date, most research for automotive applications has focused on proton exchange membrane fuel cells (PEMFCs), because these systems have demonstrated the highest power density. Recently, however, an alternative technology, hydroxide exchange membrane fuel cells (HEMFCs), has gained significant attention, because of the possibility to use stable platinum-group-metal-free catalysts, with inherent, long-term cost advantages. In this Perspective, we discuss the cost profile of PEMFCs and the advantages offered by HEMFCs. In particular, we discuss catalyst development needs for HEMFCs and set catalyst activity targets to achieve performance parity with state-of-the-art automotive PEMFCs. Meeting these targets requires careful optimization of nanostructures to pack high surface areas into a small volume, while maintaining high area-specific activity and favourable pore-transport properties.

  7. Activity targets for nanostructured platinum-group-metal-free catalysts in hydroxide exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Setzler, Brian P.; Zhuang, Zhongbin; Wittkopf, Jarrid A.; Yan, Yushan

    2016-12-01

    Fuel cells are the zero-emission automotive power source that best preserves the advantages of gasoline automobiles: low upfront cost, long driving range and fast refuelling. To make fuel-cell cars a reality, the US Department of Energy has set a fuel cell system cost target of US$30 kW-1 in the long-term, which equates to US$2,400 per vehicle, excluding several major powertrain components (in comparison, a basic, but complete, internal combustion engine system costs approximately US$3,000). To date, most research for automotive applications has focused on proton exchange membrane fuel cells (PEMFCs), because these systems have demonstrated the highest power density. Recently, however, an alternative technology, hydroxide exchange membrane fuel cells (HEMFCs), has gained significant attention, because of the possibility to use stable platinum-group-metal-free catalysts, with inherent, long-term cost advantages. In this Perspective, we discuss the cost profile of PEMFCs and the advantages offered by HEMFCs. In particular, we discuss catalyst development needs for HEMFCs and set catalyst activity targets to achieve performance parity with state-of-the-art automotive PEMFCs. Meeting these targets requires careful optimization of nanostructures to pack high surface areas into a small volume, while maintaining high area-specific activity and favourable pore-transport properties.

  8. VOLUMNECT: measuring volumes with Kinect

    NASA Astrophysics Data System (ADS)

    Quintino Ferreira, Beatriz; Griné, Miguel; Gameiro, Duarte; Costeira, João. Paulo; Sousa Santos, Beatriz

    2014-03-01

    This article presents a solution to volume measurement object packing using 3D cameras (such as the Microsoft KinectTM). We target application scenarios, such as warehouses or distribution and logistics companies, where it is important to promptly compute package volumes, yet high accuracy is not pivotal. Our application auto- matically detects cuboid objects using the depth camera data and computes their volume and sorting it allowing space optimization. The proposed methodology applies to a point cloud simple computer vision and image processing methods, as connected components, morphological operations and Harris corner detector, producing encouraging results, namely an accuracy in volume measurement of 8mm. Aspects that can be further improved are identified; nevertheless, the current solution is already promising turning out to be cost effective for the envisaged scenarios.

  9. The Fast-Casual Conundrum: Fast-Casual Restaurant Entrées Are Higher in Calories than Fast Food.

    PubMed

    Schoffman, Danielle E; Davidson, Charis R; Hales, Sarah B; Crimarco, Anthony E; Dahl, Alicia A; Turner-McGrievy, Gabrielle M

    2016-10-01

    Frequently eating fast food has been associated with consuming a diet high in calories, and there is a public perception that fast-casual restaurants (eg, Chipotle) are healthier than traditional fast food (eg, McDonald's). However, research has not examined whether fast-food entrées and fast-casual entrées differ in calorie content. The purpose of this study was to determine whether the caloric content of entrées at fast-food restaurants differed from that found at fast-casual restaurants. This study was a cross-sectional analysis of secondary data. Calorie information from 2014 for lunch and dinner entrées for fast-food and fast-casual restaurants was downloaded from the MenuStat database. Mean calories per entrée between fast-food restaurants and fast-casual restaurants and the proportion of restaurant entrées that fell into different calorie ranges were assessed. A t test was conducted to test the hypothesis that there was no difference between the average calories per entrée at fast-food and fast-casual restaurants. To examine the difference in distribution of entrées in different calorie ranges between fast-food and fast-casual restaurants, χ(2) tests were used. There were 34 fast-food and 28 fast-casual restaurants included in the analysis (n=3,193 entrées). Fast-casual entrées had significantly more calories per entrée (760±301 kcal) than fast-food entrées (561±268; P<0.0001). A greater proportion of fast-casual entrées compared with fast-food entrées exceeded the median of 640 kcal per entrée (P<0.0001). Although fast-casual entrées contained more calories than fast-food entrées in the study sample, future studies should compare actual purchasing patterns from these restaurants to determine whether the energy content or nutrient density of full meals (ie, entrées with sides and drinks) differs between fast-casual restaurants and fast-food restaurants. Calorie-conscious consumers should consider the calorie content of entrée items

  10. Scaling of Energy Deposition in Fast Ignition Targets

    NASA Astrophysics Data System (ADS)

    Campbell, R. B.; Welch, Dale

    2005-10-01

    We examine the scaling to ignition of the energy deposition of laser generated electrons in compressed fast ignition cores. Relevant cores have densities of several hundred g/cm^3, with a few keV initial temperature. As the laser intensities increase approaching ignition systems, on the order of a few 10^21W/cm^2, the hot electron energies expected to approach 100MeV[1]. Most certainly anomalous processes must play a role in the energy transfer, but the exact nature of these processes, as well as a practical way to model them, remain open issues. Traditional PIC explicit methods are limited to low densities on current and anticipated computing platforms, so the study of relevant parameter ranges has received so far little attention. We use LSP[2] to examine a relativistic electron beam (presumed generated from a laser plasma interaction) of legislated energy and angular distribution is injected into a 3D block of compressed DT. Collective effects will determine the stopping, most likely driven by magnetic field filamentation. The scaling of the stopping as a function of block density and temperature, as well as hot electron current and laser intensity is presented. Sub-grid models may be profitably used and degenerate effects included in the solution of this problem. Sandia is operated by Sandia Corporation, for the USDOE. [1] A. Pukhov, et. al., Phys. Plas. 6, p2847 (1999) [2] D. R. Welch et al., Comput. Phys.Commun. 164, p183 (2004).

  11. Deep Deconvolutional Neural Network for Target Segmentation of Nasopharyngeal Cancer in Planning Computed Tomography Images.

    PubMed

    Men, Kuo; Chen, Xinyuan; Zhang, Ye; Zhang, Tao; Dai, Jianrong; Yi, Junlin; Li, Yexiong

    2017-01-01

    Radiotherapy is one of the main treatment methods for nasopharyngeal carcinoma (NPC). It requires exact delineation of the nasopharynx gross tumor volume (GTVnx), the metastatic lymph node gross tumor volume (GTVnd), the clinical target volume (CTV), and organs at risk in the planning computed tomography images. However, this task is time-consuming and operator dependent. In the present study, we developed an end-to-end deep deconvolutional neural network (DDNN) for segmentation of these targets. The proposed DDNN is an end-to-end architecture enabling fast training and testing. It consists of two important components: an encoder network and a decoder network. The encoder network was used to extract the visual features of a medical image and the decoder network was used to recover the original resolution by deploying deconvolution. A total of 230 patients diagnosed with NPC stage I or stage II were included in this study. Data from 184 patients were chosen randomly as a training set to adjust the parameters of DDNN, and the remaining 46 patients were the test set to assess the performance of the model. The Dice similarity coefficient (DSC) was used to quantify the segmentation results of the GTVnx, GTVnd, and CTV. In addition, the performance of DDNN was compared with the VGG-16 model. The proposed DDNN method outperformed the VGG-16 in all the segmentation. The mean DSC values of DDNN were 80.9% for GTVnx, 62.3% for the GTVnd, and 82.6% for CTV, whereas VGG-16 obtained 72.3, 33.7, and 73.7% for the DSC values, respectively. DDNN can be used to segment the GTVnx and CTV accurately. The accuracy for the GTVnd segmentation was relatively low due to the considerable differences in its shape, volume, and location among patients. The accuracy is expected to increase with more training data and combination of MR images. In conclusion, DDNN has the potential to improve the consistency of contouring and streamline radiotherapy workflows, but careful human review and a

  12. Pulse shape discrimination based on fast signals from silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Yu, Junhao; Wei, Zhiyong; Fang, Meihua; Zhang, Zixia; Cheng, Can; Wang, Yi; Su, Huiwen; Ran, Youquan; Zhu, Qingwei; Zhang, He; Duan, Kai; Chen, Ming; Liu, Meng

    2018-06-01

    Recent developments in organic plastic scintillators capable of pulse shape discrimination (PSD) enable a breakthrough in discrimination between neutrons and gammas. Plastic scintillator detectors coupled with silicon photomultipliers (SiPMs) offer many advantages, such as lower power consumption, smaller volume, and especially insensitivity to magnetic fields, compared with conventional photomultiplier tubes (PMTs). A SensL SiPM has two outputs: a standard output and a fast output. It is known that the charge injected into the fast output electrode is typically approximately 2% of the total charge generated during the avalanche, whereas the charge injected into the standard output electrode is nearly 98% of the total. Fast signals from SiPMs exhibit better performance in terms of timing and time-correlated measurements compared with standard signals. The pulse duration of a standard signal is on the order of hundreds of nanoseconds, whereas the pulse duration of the main monopole waveform of a fast signal is a few tens of nanoseconds. Fast signals are traditionally thought to be suitable for photon counting at very high speeds but unsuitable for PSD due to the partial charge collection. Meanwhile, the standard outputs of SiPMs coupled with discriminating scintillators have yielded nice PSD performances, but there have been no reports on PSD using fast signals. Our analysis shows that fast signals can also provide discrimination if the rate of charge injection into the fast output electrode is fixed for each event, even though only a portion of the charge is collected. In this work, we achieved successful PSD using fast signals; meanwhile, using a coincidence timing window of less 3 nanoseconds between the readouts from both ends of the detector reduced the influence of the high SiPM dark current. We experimentally achieved good timing performance and PSD capability simultaneously.

  13. Transorbital target localization in the porcine model

    NASA Astrophysics Data System (ADS)

    DeLisi, Michael P.; Mawn, Louise A.; Galloway, Robert L.

    2013-03-01

    Current pharmacological therapies for the treatment of chronic optic neuropathies such as glaucoma are often inadequate due to their inability to directly affect the optic nerve and prevent neuron death. While drugs that target the neurons have been developed, existing methods of administration are not capable of delivering an effective dose of medication along the entire length of the nerve. We have developed an image-guided system that utilizes a magnetically tracked flexible endoscope to navigate to the back of the eye and administer therapy directly to the optic nerve. We demonstrate the capabilities of this system with a series of targeted surgical interventions in the orbits of live pigs. Target objects consisted of NMR microspherical bulbs with a volume of 18 μL filled with either water or diluted gadolinium-based contrast, and prepared with either the presence or absence of a visible coloring agent. A total of 6 pigs were placed under general anesthesia and two microspheres of differing color and contrast content were blindly implanted in the fat tissue of each orbit. The pigs were scanned with T1-weighted MRI, image volumes were registered, and the microsphere containing gadolinium contrast was designated as the target. The surgeon was required to navigate the flexible endoscope to the target and identify it by color. For the last three pigs, a 2D/3D registration was performed such that the target's coordinates in the image volume was noted and its location on the video stream was displayed with a crosshair to aid in navigation. The surgeon was able to correctly identify the target by color, with an average intervention time of 20 minutes for the first three pigs and 3 minutes for the last three.

  14. Automatic segmentation of the clinical target volume and organs at risk in the planning CT for rectal cancer using deep dilated convolutional neural networks.

    PubMed

    Men, Kuo; Dai, Jianrong; Li, Yexiong

    2017-12-01

    Delineation of the clinical target volume (CTV) and organs at risk (OARs) is very important for radiotherapy but is time-consuming and prone to inter-observer variation. Here, we proposed a novel deep dilated convolutional neural network (DDCNN)-based method for fast and consistent auto-segmentation of these structures. Our DDCNN method was an end-to-end architecture enabling fast training and testing. Specifically, it employed a novel multiple-scale convolutional architecture to extract multiple-scale context features in the early layers, which contain the original information on fine texture and boundaries and which are very useful for accurate auto-segmentation. In addition, it enlarged the receptive fields of dilated convolutions at the end of networks to capture complementary context features. Then, it replaced the fully connected layers with fully convolutional layers to achieve pixel-wise segmentation. We used data from 278 patients with rectal cancer for evaluation. The CTV and OARs were delineated and validated by senior radiation oncologists in the planning computed tomography (CT) images. A total of 218 patients chosen randomly were used for training, and the remaining 60 for validation. The Dice similarity coefficient (DSC) was used to measure segmentation accuracy. Performance was evaluated on segmentation of the CTV and OARs. In addition, the performance of DDCNN was compared with that of U-Net. The proposed DDCNN method outperformed the U-Net for all segmentations, and the average DSC value of DDCNN was 3.8% higher than that of U-Net. Mean DSC values of DDCNN were 87.7% for the CTV, 93.4% for the bladder, 92.1% for the left femoral head, 92.3% for the right femoral head, 65.3% for the intestine, and 61.8% for the colon. The test time was 45 s per patient for segmentation of all the CTV, bladder, left and right femoral heads, colon, and intestine. We also assessed our approaches and results with those in the literature: our system showed superior

  15. Transform coding for hardware-accelerated volume rendering.

    PubMed

    Fout, Nathaniel; Ma, Kwan-Liu

    2007-01-01

    Hardware-accelerated volume rendering using the GPU is now the standard approach for real-time volume rendering, although limited graphics memory can present a problem when rendering large volume data sets. Volumetric compression in which the decompression is coupled to rendering has been shown to be an effective solution to this problem; however, most existing techniques were developed in the context of software volume rendering, and all but the simplest approaches are prohibitive in a real-time hardware-accelerated volume rendering context. In this paper we present a novel block-based transform coding scheme designed specifically with real-time volume rendering in mind, such that the decompression is fast without sacrificing compression quality. This is made possible by consolidating the inverse transform with dequantization in such a way as to allow most of the reprojection to be precomputed. Furthermore, we take advantage of the freedom afforded by off-line compression in order to optimize the encoding as much as possible while hiding this complexity from the decoder. In this context we develop a new block classification scheme which allows us to preserve perceptually important features in the compression. The result of this work is an asymmetric transform coding scheme that allows very large volumes to be compressed and then decompressed in real-time while rendering on the GPU.

  16. Defining the Optimal Planning Target Volume in Image-Guided Stereotactic Radiosurgery of Brain Metastases: Results of a Randomized Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kirkpatrick, John P., E-mail: john.kirkpatrick@dm.duke.edu; Department of Surgery, Duke University, Durham, North Carolina; Wang, Zhiheng

    2015-01-01

    Purpose: To identify an optimal margin about the gross target volume (GTV) for stereotactic radiosurgery (SRS) of brain metastases, minimizing toxicity and local recurrence. Methods and Materials: Adult patients with 1 to 3 brain metastases less than 4 cm in greatest dimension, no previous brain radiation therapy, and Karnofsky performance status (KPS) above 70 were eligible for this institutional review board–approved trial. Individual lesions were randomized to 1- or 3- mm uniform expansion of the GTV defined on contrast-enhanced magnetic resonance imaging (MRI). The resulting planning target volume (PTV) was treated to 24, 18, or 15 Gy marginal dose for maximum PTV diametersmore » less than 2, 2 to 2.9, and 3 to 3.9 cm, respectively, using a linear accelerator–based image-guided system. The primary endpoint was local recurrence (LR). Secondary endpoints included neurocognition Mini-Mental State Examination, Trail Making Test Parts A and B, quality of life (Functional Assessment of Cancer Therapy-Brain), radionecrosis (RN), need for salvage radiation therapy, distant failure (DF) in the brain, and overall survival (OS). Results: Between February 2010 and November 2012, 49 patients with 80 brain metastases were treated. The median age was 61 years, the median KPS was 90, and the predominant histologies were non–small cell lung cancer (25 patients) and melanoma (8). Fifty-five, 19, and 6 lesions were treated to 24, 18, and 15 Gy, respectively. The PTV/GTV ratio, volume receiving 12 Gy or more, and minimum dose to PTV were significantly higher in the 3-mm group (all P<.01), and GTV was similar (P=.76). At a median follow-up time of 32.2 months, 11 patients were alive, with median OS 10.6 months. LR was observed in only 3 lesions (2 in the 1 mm group, P=.51), with 6.7% LR 12 months after SRS. Biopsy-proven RN alone was observed in 6 lesions (5 in the 3-mm group, P=.10). The 12-month DF rate was 45.7%. Three months after SRS, no significant change

  17. Defining the optimal planning target volume in image-guided stereotactic radiosurgery of brain metastases: results of a randomized trial.

    PubMed

    Kirkpatrick, John P; Wang, Zhiheng; Sampson, John H; McSherry, Frances; Herndon, James E; Allen, Karen J; Duffy, Eileen; Hoang, Jenny K; Chang, Zheng; Yoo, David S; Kelsey, Chris R; Yin, Fang-Fang

    2015-01-01

    To identify an optimal margin about the gross target volume (GTV) for stereotactic radiosurgery (SRS) of brain metastases, minimizing toxicity and local recurrence. Adult patients with 1 to 3 brain metastases less than 4 cm in greatest dimension, no previous brain radiation therapy, and Karnofsky performance status (KPS) above 70 were eligible for this institutional review board-approved trial. Individual lesions were randomized to 1- or 3- mm uniform expansion of the GTV defined on contrast-enhanced magnetic resonance imaging (MRI). The resulting planning target volume (PTV) was treated to 24, 18, or 15 Gy marginal dose for maximum PTV diameters less than 2, 2 to 2.9, and 3 to 3.9 cm, respectively, using a linear accelerator-based image-guided system. The primary endpoint was local recurrence (LR). Secondary endpoints included neurocognition Mini-Mental State Examination, Trail Making Test Parts A and B, quality of life (Functional Assessment of Cancer Therapy-Brain), radionecrosis (RN), need for salvage radiation therapy, distant failure (DF) in the brain, and overall survival (OS). Between February 2010 and November 2012, 49 patients with 80 brain metastases were treated. The median age was 61 years, the median KPS was 90, and the predominant histologies were non-small cell lung cancer (25 patients) and melanoma (8). Fifty-five, 19, and 6 lesions were treated to 24, 18, and 15 Gy, respectively. The PTV/GTV ratio, volume receiving 12 Gy or more, and minimum dose to PTV were significantly higher in the 3-mm group (all P<.01), and GTV was similar (P=.76). At a median follow-up time of 32.2 months, 11 patients were alive, with median OS 10.6 months. LR was observed in only 3 lesions (2 in the 1 mm group, P=.51), with 6.7% LR 12 months after SRS. Biopsy-proven RN alone was observed in 6 lesions (5 in the 3-mm group, P=.10). The 12-month DF rate was 45.7%. Three months after SRS, no significant change in neurocognition or quality of life was observed. SRS was well

  18. Geometric convex cone volume analysis

    NASA Astrophysics Data System (ADS)

    Li, Hsiao-Chi; Chang, Chein-I.

    2016-05-01

    Convexity is a major concept used to design and develop endmember finding algorithms (EFAs). For abundance unconstrained techniques, Pixel Purity Index (PPI) and Automatic Target Generation Process (ATGP) which use Orthogonal Projection (OP) as a criterion, are commonly used method. For abundance partially constrained techniques, Convex Cone Analysis is generally preferred which makes use of convex cones to impose Abundance Non-negativity Constraint (ANC). For abundance fully constrained N-FINDR and Simplex Growing Algorithm (SGA) are most popular methods which use simplex volume as a criterion to impose ANC and Abundance Sum-to-one Constraint (ASC). This paper analyze an issue encountered in volume calculation with a hyperplane introduced to illustrate an idea of bounded convex cone. Geometric Convex Cone Volume Analysis (GCCVA) projects the boundary vectors of a convex cone orthogonally on a hyperplane to reduce the effect of background signatures and a geometric volume approach is applied to address the issue arose from calculating volume and further improve the performance of convex cone-based EFAs.

  19. CAFNA{reg{underscore}sign}, coded aperture fast neutron analysis for contraband detection: Preliminary results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, L.; Lanza, R.C.

    1999-12-01

    The authors have developed a near field coded aperture imaging system for use with fast neutron techniques as a tool for the detection of contraband and hidden explosives through nuclear elemental analysis. The technique relies on the prompt gamma rays produced by fast neutron interactions with the object being examined. The position of the nuclear elements is determined by the location of the gamma emitters. For existing fast neutron techniques, in Pulsed Fast Neutron Analysis (PFNA), neutrons are used with very low efficiency; in Fast Neutron Analysis (FNS), the sensitivity for detection of the signature gamma rays is very low.more » For the Coded Aperture Fast Neutron Analysis (CAFNA{reg{underscore}sign}) the authors have developed, the efficiency for both using the probing fast neutrons and detecting the prompt gamma rays is high. For a probed volume of n{sup 3} volume elements (voxels) in a cube of n resolution elements on a side, they can compare the sensitivity with other neutron probing techniques. As compared to PFNA, the improvement for neutron utilization is n{sup 2}, where the total number of voxels in the object being examined is n{sup 3}. Compared to FNA, the improvement for gamma-ray imaging is proportional to the total open area of the coded aperture plane; a typical value is n{sup 2}/2, where n{sup 2} is the number of total detector resolution elements or the number of pixels in an object layer. It should be noted that the actual signal to noise ratio of a system depends also on the nature and distribution of background events and this comparison may reduce somewhat the effective sensitivity of CAFNA. They have performed analysis, Monte Carlo simulations, and preliminary experiments using low and high energy gamma-ray sources. The results show that a high sensitivity 3-D contraband imaging and detection system can be realized by using CAFNA.« less

  20. Sphaeropsidin A shows promising activity against drug-resistant cancer cells by targeting regulatory volume increase.

    PubMed

    Mathieu, Véronique; Chantôme, Aurélie; Lefranc, Florence; Cimmino, Alessio; Miklos, Walter; Paulitschke, Verena; Mohr, Thomas; Maddau, Lucia; Kornienko, Alexander; Berger, Walter; Vandier, Christophe; Evidente, Antonio; Delpire, Eric; Kiss, Robert

    2015-10-01

    Despite the recent advances in the treatment of tumors with intrinsic chemotherapy resistance, such as melanoma and renal cancers, their prognosis remains poor and new chemical agents with promising activity against these cancers are urgently needed. Sphaeropsidin A, a fungal metabolite whose anticancer potential had previously received little attention, was isolated from Diplodia cupressi and found to display specific anticancer activity in vitro against melanoma and kidney cancer subpanels in the National Cancer Institute (NCI) 60-cell line screen. The NCI data revealed a mean LC50 of ca. 10 µM and a cellular sensitivity profile that did not match that of any other agent in the 765,000 compound database. Subsequent mechanistic studies in melanoma and other multidrug-resistant in vitro cancer models showed that sphaeropsidin A can overcome apoptosis as well as multidrug resistance by inducing a marked and rapid cellular shrinkage related to the loss of intracellular Cl(-) and the decreased HCO3 (-) concentration in the culture supernatant. These changes in ion homeostasis and the absence of effects on the plasma membrane potential were attributed to the sphaeropsidin A-induced impairment of regulatory volume increase (RVI). Preliminary results also indicate that depending on the type of cancer, the sphaeropsidin A effects on RVI could be related to Na-K-2Cl electroneutral cotransporter or Cl(-)/HCO3 (-) anion exchanger(s) targeting. This study underscores the modulation of ion-transporter activity as a promising therapeutic strategy to combat drug-resistant cancers and identifies the fungal metabolite, sphaeropsidin A, as a lead to develop anticancer agents targeting RVI in cancer cells.

  1. Automated linking of suspicious findings between automated 3D breast ultrasound volumes

    NASA Astrophysics Data System (ADS)

    Gubern-Mérida, Albert; Tan, Tao; van Zelst, Jan; Mann, Ritse M.; Karssemeijer, Nico

    2016-03-01

    Automated breast ultrasound (ABUS) is a 3D imaging technique which is rapidly emerging as a safe and relatively inexpensive modality for screening of women with dense breasts. However, reading ABUS examinations is very time consuming task since radiologists need to manually identify suspicious findings in all the different ABUS volumes available for each patient. Image analysis techniques to automatically link findings across volumes are required to speed up clinical workflow and make ABUS screening more efficient. In this study, we propose an automated system to, given the location in the ABUS volume being inspected (source), find the corresponding location in a target volume. The target volume can be a different view of the same study or the same view from a prior examination. The algorithm was evaluated using 118 linkages between suspicious abnormalities annotated in a dataset of ABUS images of 27 patients participating in a high risk screening program. The distance between the predicted location and the center of the annotated lesion in the target volume was computed for evaluation. The mean ± stdev and median distance error achieved by the presented algorithm for linkages between volumes of the same study was 7.75±6.71 mm and 5.16 mm, respectively. The performance was 9.54±7.87 and 8.00 mm (mean ± stdev and median) for linkages between volumes from current and prior examinations. The proposed approach has the potential to minimize user interaction for finding correspondences among ABUS volumes.

  2. Atlas-based automatic segmentation of head and neck organs at risk and nodal target volumes: a clinical validation.

    PubMed

    Daisne, Jean-François; Blumhofer, Andreas

    2013-06-26

    Intensity modulated radiotherapy for head and neck cancer necessitates accurate definition of organs at risk (OAR) and clinical target volumes (CTV). This crucial step is time consuming and prone to inter- and intra-observer variations. Automatic segmentation by atlas deformable registration may help to reduce time and variations. We aim to test a new commercial atlas algorithm for automatic segmentation of OAR and CTV in both ideal and clinical conditions. The updated Brainlab automatic head and neck atlas segmentation was tested on 20 patients: 10 cN0-stages (ideal population) and 10 unselected N-stages (clinical population). Following manual delineation of OAR and CTV, automatic segmentation of the same set of structures was performed and afterwards manually corrected. Dice Similarity Coefficient (DSC), Average Surface Distance (ASD) and Maximal Surface Distance (MSD) were calculated for "manual to automatic" and "manual to corrected" volumes comparisons. In both groups, automatic segmentation saved about 40% of the corresponding manual segmentation time. This effect was more pronounced for OAR than for CTV. The edition of the automatically obtained contours significantly improved DSC, ASD and MSD. Large distortions of normal anatomy or lack of iodine contrast were the limiting factors. The updated Brainlab atlas-based automatic segmentation tool for head and neck Cancer patients is timesaving but still necessitates review and corrections by an expert.

  3. [Definition of nodal volumes in breast cancer treatment and segmentation guidelines].

    PubMed

    Kirova, Y M; Castro Pena, P; Dendale, R; Campana, F; Bollet, M A; Fournier-Bidoz, N; Fourquet, A

    2009-06-01

    To assist in the determination of breast and nodal volumes in the setting of radiotherapy for breast cancer and establish segmentation guidelines. Materials and methods. Contrast metarial enhanced CT examinations were obtained in the treatment position in 25 patients to clearly define the target volumes. The clinical target volume (CTV) including the breast, internal mammary nodes, supraclavicular and subclavicular regions and axxilary region were segmented along with the brachial plexus and interpectoral nodes. The following critical organs were also segmented: heart, lungs, contralateral breast, thyroid, esophagus and humeral head. A correlation between clinical and imaging findings and meeting between radiation oncologists and breast specialists resulted in a better definition of irradiation volumes for breast and nodes with establishement of segmentation guidelines and creation of an anatomical atlas. A practical approach, based on anatomical criteria, is proposed to assist in the segmentation of breast and node volumes in the setting of breast cancer treatment along with a definition of irradiation volumes.

  4. Relative and absolute availability of fast-food restaurants in relation to the development of diabetes: A population-based cohort study.

    PubMed

    Polsky, Jane Y; Moineddin, Rahim; Glazier, Richard H; Dunn, James R; Booth, Gillian L

    2016-06-09

    To determine whether residents living in areas with a high proportion of fast-food restaurants (FFR) relative to all restaurants are more likely to develop diabetes and whether the risk varies according to the volume of FFR. The study cohort consisted of adult respondents (20-84 years) to the Canadian Community Health Survey (cycles 2005, 2007/2008, 2009/2010) who resided within walking distance (720 m) of at least one restaurant in Toronto, Brampton, Mississauga or Hamilton, ON. The development of diabetes was established by linking participants to the Ontario Diabetes Database. Cox proportional hazards models were used to estimate hazard ratios (HRs) of incident diabetes associated with relative and absolute measures of restaurant availability. During a median follow-up of 5 years, 347 of 7,079 participants (4.6%) developed diabetes. Among younger adults (20-65 years, n = 5,806), a greater proportion of fast-food relative to all restaurants was significantly associated with incident diabetes after adjustment for a range of individual and area-level covariates, but only in areas with high volumes of fast-food retailers (3+ outlets) (HR = 1.79, 95% confidence interval: 1.03-3.12, across the interquartile range). Adjusting for body mass index rendered this association non-significant. No significant associations were observed in areas with low volumes of FFR or among older adults (65-84 years, n = 1,273). Absolute availability (number) of fast-food and other restaurants was generally unrelated to incident diabetes. Areas with the double burden of a high volume of FFR and few dining alternatives may represent an adverse environment for the development of diabetes.

  5. Myomaker mediates fusion of fast myocytes in zebrafish embryos

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Landemaine, Aurélie; Rescan, Pierre-Yves; Gabillard, Jean-Charles, E-mail: Jean-charles.gabillard@rennes.inra.fr

    2014-09-05

    Highlights: • Myomaker is transiently expressed in fast myocytes during embryonic myogenesis. • Myomaker is essential for fast myocyte fusion in zebrafish. • The function of myomaker is conserved among Teleostomi. - Abstract: Myomaker (also called Tmem8c), a new membrane activator of myocyte fusion was recently discovered in mice. Using whole mount in situ hybridization on zebrafish embryos at different stages of embryonic development, we show that myomaker is transiently expressed in fast myocytes forming the bulk of zebrafish myotome. Zebrafish embryos injected with morpholino targeted against myomaker were alive after yolk resorption and appeared morphologically normal, but they weremore » unable to swim, even under effect of a tactile stimulation. Confocal observations showed a marked phenotype characterized by the persistence of mononucleated muscle cells in the fast myotome at developmental stages where these cells normally fuse to form multinucleated myotubes. This indicates that myomaker is essential for myocyte fusion in zebrafish. Thus, there is an evolutionary conservation of myomaker expression and function among Teleostomi.« less

  6. [Target volume segmentation of PET images by an iterative method based on threshold value].

    PubMed

    Castro, P; Huerga, C; Glaría, L A; Plaza, R; Rodado, S; Marín, M D; Mañas, A; Serrada, A; Núñez, L

    2014-01-01

    An automatic segmentation method is presented for PET images based on an iterative approximation by threshold value that includes the influence of both lesion size and background present during the acquisition. Optimal threshold values that represent a correct segmentation of volumes were determined based on a PET phantom study that contained different sizes spheres and different known radiation environments. These optimal values were normalized to background and adjusted by regression techniques to a two-variable function: lesion volume and signal-to-background ratio (SBR). This adjustment function was used to build an iterative segmentation method and then, based in this mention, a procedure of automatic delineation was proposed. This procedure was validated on phantom images and its viability was confirmed by retrospectively applying it on two oncology patients. The resulting adjustment function obtained had a linear dependence with the SBR and was inversely proportional and negative with the volume. During the validation of the proposed method, it was found that the volume deviations respect to its real value and CT volume were below 10% and 9%, respectively, except for lesions with a volume below 0.6 ml. The automatic segmentation method proposed can be applied in clinical practice to tumor radiotherapy treatment planning in a simple and reliable way with a precision close to the resolution of PET images. Copyright © 2013 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  7. Lysine Acetylation of CREBH Regulates Fasting-Induced Hepatic Lipid Metabolism

    PubMed Central

    Kim, Hyunbae; Mendez, Roberto; Chen, Xuequn; Fang, Deyu

    2015-01-01

    Cyclic AMP-responsive element-binding protein 3-like 3, hepatocyte specific (CREBH), is a hepatic transcription factor that functions as a key regulator of energy homeostasis. Here, we defined a regulatory CREBH posttranslational modification process, namely, lysine-specific acetylation, and its functional involvement in fasting-induced hepatic lipid metabolism. Fasting induces CREBH acetylation in mouse livers in a time-dependent manner, and this event is critical for CREBH transcriptional activity in regulating hepatic lipid homeostasis. The histone acetyltransferase PCAF-mediated acetylation and the deacetylase sirtuin-1-mediated deacetylation coexist to maintain CREBH acetylation states under fasting conditions. Site-directed mutagenesis and functional analyses revealed that the lysine (K) residue at position 294 (K294) within the bZIP domain of the CREBH protein is the site where fasting-induced acetylation/deacetylation occurs. Introduction of the acetylation-deficient (K294R) or acetylation-mimicking (K294Q) mutation inhibited or enhanced CREBH transcriptional activity, respectively. Importantly, CREBH acetylation at lysine 294 was required for the interaction and synergy between CREBH and peroxisome proliferator-activated receptor α (PPARα) in activating their target genes upon fasting or glucagon stimulation. Introduction of the CREBH lysine 294 mutation in the liver leads to hepatic steatosis and hyperlipidemia in animals under prolonged fasting. In summary, our study reveals a molecular mechanism by which fasting or glucagon stimulation modulates lipid homeostasis through acetylation of CREBH. PMID:26438600

  8. Target-Pathogen: a structural bioinformatic approach to prioritize drug targets in pathogens.

    PubMed

    Sosa, Ezequiel J; Burguener, Germán; Lanzarotti, Esteban; Defelipe, Lucas; Radusky, Leandro; Pardo, Agustín M; Marti, Marcelo; Turjanski, Adrián G; Fernández Do Porto, Darío

    2018-01-04

    Available genomic data for pathogens has created new opportunities for drug discovery and development to fight them, including new resistant and multiresistant strains. In particular structural data must be integrated with both, gene information and experimental results. In this sense, there is a lack of an online resource that allows genome wide-based data consolidation from diverse sources together with thorough bioinformatic analysis that allows easy filtering and scoring for fast target selection for drug discovery. Here, we present Target-Pathogen database (http://target.sbg.qb.fcen.uba.ar/patho), designed and developed as an online resource that allows the integration and weighting of protein information such as: function, metabolic role, off-targeting, structural properties including druggability, essentiality and omic experiments, to facilitate the identification and prioritization of candidate drug targets in pathogens. We include in the database 10 genomes of some of the most relevant microorganisms for human health (Mycobacterium tuberculosis, Mycobacterium leprae, Klebsiella pneumoniae, Plasmodium vivax, Toxoplasma gondii, Leishmania major, Wolbachia bancrofti, Trypanosoma brucei, Shigella dysenteriae and Schistosoma Smanosoni) and show its applicability. New genomes can be uploaded upon request. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  9. Target-Pathogen: a structural bioinformatic approach to prioritize drug targets in pathogens

    PubMed Central

    Sosa, Ezequiel J; Burguener, Germán; Lanzarotti, Esteban; Radusky, Leandro; Pardo, Agustín M; Marti, Marcelo

    2018-01-01

    Abstract Available genomic data for pathogens has created new opportunities for drug discovery and development to fight them, including new resistant and multiresistant strains. In particular structural data must be integrated with both, gene information and experimental results. In this sense, there is a lack of an online resource that allows genome wide-based data consolidation from diverse sources together with thorough bioinformatic analysis that allows easy filtering and scoring for fast target selection for drug discovery. Here, we present Target-Pathogen database (http://target.sbg.qb.fcen.uba.ar/patho), designed and developed as an online resource that allows the integration and weighting of protein information such as: function, metabolic role, off-targeting, structural properties including druggability, essentiality and omic experiments, to facilitate the identification and prioritization of candidate drug targets in pathogens. We include in the database 10 genomes of some of the most relevant microorganisms for human health (Mycobacterium tuberculosis, Mycobacterium leprae, Klebsiella pneumoniae, Plasmodium vivax, Toxoplasma gondii, Leishmania major, Wolbachia bancrofti, Trypanosoma brucei, Shigella dysenteriae and Schistosoma Smanosoni) and show its applicability. New genomes can be uploaded upon request. PMID:29106651

  10. Volumetric-modulated arc therapy for the treatment of a large planning target volume in thoracic esophageal cancer.

    PubMed

    Abbas, Ahmar S; Moseley, Douglas; Kassam, Zahra; Kim, Sun Mo; Cho, Charles

    2013-05-06

    Recently, volumetric-modulated arc therapy (VMAT) has demonstrated the ability to deliver radiation dose precisely and accurately with a shorter delivery time compared to conventional intensity-modulated fixed-field treatment (IMRT). We applied the hypothesis of VMAT technique for the treatment of thoracic esophageal carcinoma to determine superior or equivalent conformal dose coverage for a large thoracic esophageal planning target volume (PTV) with superior or equivalent sparing of organs-at-risk (OARs) doses, and reduce delivery time and monitor units (MUs), in comparison with conventional fixed-field IMRT plans. We also analyzed and compared some other important metrics of treatment planning and treatment delivery for both IMRT and VMAT techniques. These metrics include: 1) the integral dose and the volume receiving intermediate dose levels between IMRT and VMATI plans; 2) the use of 4D CT to determine the internal motion margin; and 3) evaluating the dosimetry of every plan through patient-specific QA. These factors may impact the overall treatment plan quality and outcomes from the individual planning technique used. In this study, we also examined the significance of using two arcs vs. a single-arc VMAT technique for PTV coverage, OARs doses, monitor units and delivery time. Thirteen patients, stage T2-T3 N0-N1 (TNM AJCC 7th edn.), PTV volume median 395 cc (range 281-601 cc), median age 69 years (range 53 to 85), were treated from July 2010 to June 2011 with a four-field (n = 4) or five-field (n = 9) step-and-shoot IMRT technique using a 6 MV beam to a prescribed dose of 50 Gy in 20 to 25 F. These patients were retrospectively replanned using single arc (VMATI, 91 control points) and two arcs (VMATII, 182 control points). All treatment plans of the 13 study cases were evaluated using various dose-volume metrics. These included PTV D99, PTV D95, PTV V9547.5Gy(95%), PTV mean dose, Dmax, PTV dose conformity (Van't Riet conformation number (CN)), mean lung dose

  11. Volumetric‐modulated arc therapy for the treatment of a large planning target volume in thoracic esophageal cancer

    PubMed Central

    Moseley, Douglas; Kassam, Zahra; Kim, Sun Mo; Cho, Charles

    2013-01-01

    Recently, volumetric‐modulated arc therapy (VMAT) has demonstrated the ability to deliver radiation dose precisely and accurately with a shorter delivery time compared to conventional intensity‐modulated fixed‐field treatment (IMRT). We applied the hypothesis of VMAT technique for the treatment of thoracic esophageal carcinoma to determine superior or equivalent conformal dose coverage for a large thoracic esophageal planning target volume (PTV) with superior or equivalent sparing of organs‐at‐risk (OARs) doses, and reduce delivery time and monitor units (MUs), in comparison with conventional fixed‐field IMRT plans. We also analyzed and compared some other important metrics of treatment planning and treatment delivery for both IMRT and VMAT techniques. These metrics include: 1) the integral dose and the volume receiving intermediate dose levels between IMRT and VMATI plans; 2) the use of 4D CT to determine the internal motion margin; and 3) evaluating the dosimetry of every plan through patient‐specific QA. These factors may impact the overall treatment plan quality and outcomes from the individual planning technique used. In this study, we also examined the significance of using two arcs vs. a single‐arc VMAT technique for PTV coverage, OARs doses, monitor units and delivery time. Thirteen patients, stage T2‐T3 N0‐N1 (TNM AJCC 7th edn.), PTV volume median 395 cc (range 281–601 cc), median age 69 years (range 53 to 85), were treated from July 2010 to June 2011 with a four‐field (n=4) or five‐field (n=9) step‐and‐shoot IMRT technique using a 6 MV beam to a prescribed dose of 50 Gy in 20 to 25 F. These patients were retrospectively replanned using single arc (VMATI, 91 control points) and two arcs (VMATII, 182 control points). All treatment plans of the 13 study cases were evaluated using various dose‐volume metrics. These included PTV D99, PTV D95, PTV V9547.5Gy(95%), PTV mean dose, Dmax, PTV dose conformity (Van't Riet conformation

  12. Voluntary Deep Inspiration Breath-hold Reduces the Heart Dose Without Compromising the Target Volume Coverage During Radiotherapy for Left-sided Breast Cancer.

    PubMed

    Al-Hammadi, Noora; Caparrotti, Palmira; Naim, Carole; Hayes, Jillian; Rebecca Benson, Katherine; Vasic, Ana; Al-Abdulla, Hissa; Hammoud, Rabih; Divakar, Saju; Petric, Primoz

    2018-03-01

    During radiotherapy of left-sided breast cancer, parts of the heart are irradiated, which may lead to late toxicity. We report on the experience of single institution with cardiac-sparing radiotherapy using voluntary deep inspiration breath hold (V-DIBH) and compare its dosimetric outcome with free breathing (FB) technique. Left-sided breast cancer patients, treated at our department with postoperative radiotherapy of breast/chest wall +/- regional lymph nodes between May 2015 and January 2017, were considered for inclusion. FB-computed tomography (CT) was obtained and dose-planning performed. Cases with cardiac V25Gy ≥ 5% or risk factors for heart disease were coached for V-DIBH. Compliant patients were included. They underwent additional CT in V-DIBH for planning, followed by V-DIBH radiotherapy. Dose volume histogram parameters for heart, lung and optimized planning target volume (OPTV) were compared between FB and BH. Treatment setup shifts and systematic and random errors for V-DIBH technique were compared with FB historic control. Sixty-three patients were considered for V-DIBH. Nine (14.3%) were non-compliant at coaching, leaving 54 cases for analysis. When compared with FB, V-DIBH resulted in a significant reduction of mean cardiac dose from 6.1 +/- 2.5 to 3.2 +/- 1.4 Gy (p < 0.001), maximum cardiac dose from 51.1 +/- 1.4 to 48.5 +/- 6.8 Gy (p = 0.005) and cardiac V25Gy from 8.5 +/- 4.2 to 3.2 +/- 2.5% (p < 0.001). Heart volumes receiving low (10-20 Gy) and high (30-50 Gy) doses were also significantly reduced. Mean dose to the left anterior coronary artery was 23.0 (+/- 6.7) Gy and 14.8 (+/- 7.6) Gy on FB and V-DIBH, respectively (p < 0.001). Differences between FB- and V-DIBH-derived mean lung dose (11.3 +/- 3.2 vs. 10.6 +/- 2.6 Gy), lung V20Gy (20.5 +/- 7 vs. 19.5 +/- 5.1 Gy) and V95% for the OPTV (95.6 +/- 4.1 vs. 95.2 +/- 6.3%) were non-significant. V-DIBH-derived mean shifts for initial patient setup were ≤ 2.7 mm. Random and systematic errors

  13. Sphere of equivalence--a novel target volume concept for intraoperative radiotherapy using low-energy X rays.

    PubMed

    Herskind, Carsten; Griebel, Jürgen; Kraus-Tiefenbacher, Uta; Wenz, Frederik

    2008-12-01

    Accelerated partial breast radiotherapy with low-energy photons from a miniature X-ray machine is undergoing a randomized clinical trial (Targeted Intra-operative Radiation Therapy [TARGIT]) in a selected subgroup of patients treated with breast-conserving surgery. The steep radial dose gradient implies reduced tumor cell control with increasing depth in the tumor bed. The purpose was to compare the expected risk of local recurrence in this nonuniform radiation field with that after conventional external beam radiotherapy. The relative biologic effectiveness of low-energy photons was modeled using the linear-quadratic formalism including repair of sublethal lesions during protracted irradiation. Doses of 50-kV X-rays (Intrabeam) were converted to equivalent fractionated doses, EQD2, as function of depth in the tumor bed. The probability of local control was estimated using a logistic dose-response relationship fitted to clinical data from fractionated radiotherapy. The model calculations show that, for a cohort of patients, the increase in local control in the high-dose region near the applicator partly compensates the reduction of local control at greater distances. Thus a "sphere of equivalence" exists within which the risk of recurrence is equal to that after external fractionated radiotherapy. The spatial distribution of recurrences inside this sphere will be different from that after conventional radiotherapy. A novel target volume concept is presented here. The incidence of recurrences arising in the tumor bed around the excised tumor will test the validity of this concept and the efficacy of the treatment. Recurrences elsewhere will have implications for the rationale of TARGIT.

  14. Availability of healthier options in traditional and nontraditional rural fast-food outlets

    PubMed Central

    Creel, Jennifer S; Sharkey, Joseph R; McIntosh, Alex; Anding, Jenna; Huber, J Charles

    2008-01-01

    Background Food prepared away from home has become increasingly popular to U.S. families, and may contribute to obesity. Sales have been dominated by fast food outlets, where meals are purchased for dining away from home or in the home. Although national chain affiliated fast-food outlets are considered the main source for fast food, fast foods are increasingly available in convenience stores and supermarkets/grocery stores. In rural areas, these nontraditional fast-food outlets may provide most of the opportunities for procurement of fast foods. Methods Using all traditional and nontraditio nal fast-food outlets identified in six counties in rural Texas, the type and number of regular and healthiermenu options were surveyed using on-site observation in all food venues that were primarily fast food, supermarket/grocery store, and convenience store and compared with 2005 Dietary Guidelines. Results Traditional fast-food outlets represented 84 (41%) of the 205 opportunities for procurement of fast food; 109 (53.2%) were convenience stores and 12 (5.8%) supermarkets/grocery stores. Although a s imilar variety of regular breakfast and lunch/dinner entrées were available in traditional fast-food outlets and convenience stores, the variety of healthier breakfast and lunch/dinner entrées was significantly greater in fast food outlets. Compared with convenience stores, supermarkets/grocery stores provided a greater variety of regular and healthier entrées and lunch/dinner side dishes. Conclusion Convenience stores and supermarkets/grocery stores more than double the potential access to fast foods in this rural area than traditional fast-food outlets alone; however, traditional fast food outlets offer greater opportunity for healthier fast food options than convenience stores. A complete picture of fast food environment and the availability of healthier fast food options are essential to understand environmental influences on diet and health outcomes, and identify

  15. Nail-like targets for laser plasma interaction experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pasley, J; Wei, M; Shipton, E

    2007-12-18

    The interaction of ultra-high power picosecond laser pulses with solid targets is of interest both for benchmarking the results of hybrid particle in cell (PIC) codes and also for applications to re-entrant cone guided fast ignition. We describe the construction of novel targets in which copper/titanium wires are formed into 'nail-like' objects by a process of melting and micromachining, so that energy can be reliably coupled to a 24 {micro}m diameter wire. An extreme-ultraviolet image of the interaction of the Titan laser with such a target is shown.

  16. Interpretation of HbA1c : association with mean cell volume and haemoglobin concentration.

    PubMed

    Simmons, D; Hlaing, T

    2014-11-01

    The utility of HbA1c in diabetes diagnosis is reduced in settings associated with altered haemoglobin glycation. We have studied whether HbA1c varies with mean cell volume and mean cell haemoglobin concentration as measures of haemoglobin metabolism. Randomly selected adults from rural Victoria, Australia, were invited for biomedical assessment. After excluding patients with known diabetes and/or serum creatinine ≥ 0.12 mmol/l, 1315 adults were included. Demography, arthropometric measurements, oral glucose tolerance test, analyses of full blood count and HbA1c were undertaken. After adjusting for age, sex, ethnicity, BMI, town and socio-economic status, there were no significant differences in haemoglobin, mean cell volume or mean cell haemoglobin concentration by glycaemic status (defined by oral glucose tolerance test). HbA1c was significantly and independently associated with fasting glucose, town, mean cell haemoglobin concentration, ethnicity, age and BMI among men < 50 years (R² = 33.8%); fasting glucose, 2-h glucose, mean cell haemoglobin concentration and town among men ≥ 50 years (R² = 47.9%); fasting glucose, mean cell volume, mean cell haemoglobin concentration, town, 2-h glucose and age among women < 50 years (R² = 46.3%); fasting glucose, mean cell haemoglobin concentration, mean cell volume and 2-h glucose among women ≥ 50 years (R² = 51.6%). A generalized linear model showed a gradient from an adjusted mean HbA1c of 36 (95% CI 34-38) mmol/mol with a mean cell haemoglobin concentration of ≤ 320 g/l to 30 (95% CI 29-31) mmol/mol with a mean cell haemoglobin concentration of > 370 g/l. The gradient across mean cell volume was negative, but only by 1 mmol/mol (0.1%) HbA1c . A mean HbA1c difference of 5 mmol/mol (0.5%) across the mean cell haemoglobin concentration reference range suggests that an accompanying full blood count examination may be required for its use in the diagnosis of diabetes. Further studies are required to confirm this.

  17. Fasting and 17β-estradiol differentially modulate the M-current in neuropeptide Y neurons.

    PubMed

    Roepke, Troy A; Qiu, Jian; Smith, Arik W; Rønnekleiv, Oline K; Kelly, Martin J

    2011-08-17

    Multiple K(+) conductances are targets for many peripheral and central signals involved in the control of energy homeostasis. Potential K(+) channel targets are the KCNQ subunits that form the channels underlying the M-current, a subthreshold, non-inactivating K(+) current that is a common target for G-protein-coupled receptors. Whole-cell recordings were made from GFP (Renilla)-tagged neuropeptide Y (NPY) neurons from the arcuate nucleus of the hypothalamus using protocols to isolate and characterize the M-current in these orexigenic neurons. We recorded robust K(+) currents in the voltage range of the M-current, which were inhibited by the selective KCNQ channel blocker 10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone dihydrochloride (XE991) (40 μm), in both intact males and ovariectomized, 17β-estradiol (E2)-treated females. Since NPY neurons are orexigenic and are active during fasting, the M-current was measured in fed and fasted male mice. Fasting attenuated the XE991-sensitive current by threefold, which correlated with decreased expression of the KCNQ2 and KCNQ3 subunits as measured with quantitative real-time PCR. Furthermore, E2 treatment augmented the XE991-sensitive M-current by threefold in ovariectomized (vs oil-treated) female mice. E2 treatment increased the expression of the KCNQ5 subunit in females but not KCNQ2 or KCNQ3 subunits. Fasting in females abrogated the effects of E2 on M-current activity, at least in part, by decreasing KCNQ2 and KCNQ3 expression. In summary, these data suggest that the M-current plays a pivotal role in the modulation of NPY neuronal excitability and may be an important cellular target for neurotransmitter and hormonal signals in the control of energy homeostasis in both males and females.

  18. Investigation of tDCS volume conduction effects in a highly realistic head model

    NASA Astrophysics Data System (ADS)

    Wagner, S.; Rampersad, S. M.; Aydin, Ü.; Vorwerk, J.; Oostendorp, T. F.; Neuling, T.; Herrmann, C. S.; Stegeman, D. F.; Wolters, C. H.

    2014-02-01

    Objective. We investigate volume conduction effects in transcranial direct current stimulation (tDCS) and present a guideline for efficient and yet accurate volume conductor modeling in tDCS using our newly-developed finite element (FE) approach. Approach. We developed a new, accurate and fast isoparametric FE approach for high-resolution geometry-adapted hexahedral meshes and tissue anisotropy. To attain a deeper insight into tDCS, we performed computer simulations, starting with a homogenized three-compartment head model and extending this step by step to a six-compartment anisotropic model. Main results. We are able to demonstrate important tDCS effects. First, we find channeling effects of the skin, the skull spongiosa and the cerebrospinal fluid compartments. Second, current vectors tend to be oriented towards the closest higher conducting region. Third, anisotropic WM conductivity causes current flow in directions more parallel to the WM fiber tracts. Fourth, the highest cortical current magnitudes are not only found close to the stimulation sites. Fifth, the median brain current density decreases with increasing distance from the electrodes. Significance. Our results allow us to formulate a guideline for volume conductor modeling in tDCS. We recommend to accurately model the major tissues between the stimulating electrodes and the target areas, while for efficient yet accurate modeling, an exact representation of other tissues is less important. Because for the low-frequency regime in electrophysiology the quasi-static approach is justified, our results should also be valid for at least low-frequency (e.g., below 100 Hz) transcranial alternating current stimulation.

  19. Effects of feeding and fasting on wolf blood and urine characteristics

    USGS Publications Warehouse

    DelGiudice, G.D.; Seal, U.S.; Mech, L.D.

    1987-01-01

    Feeding and fasting trials were conducted with 2 groups (A and B) of 4 gray wolves (Canis lupus) each during January 1980. The groups were fed for 9 days and fasted for 10 days in a cross-over design. Blood and urine samples and weight data were collected every 2-3 days during each trial. Hemoglobin (Hb) concentrations, red blood cell (RBC) counts, and hematocrits (HCT) were elevated in both groups during fasting. White blood cell (WBC) counts, serum urea nitrogen (SUN), triiodothyronine (T3), and insulin concentrations decreased during fasting in Groups A and B. Mean corpuscular hemoglobin concentration (MCHC), serum cholesterol, triglyceride, and iron (Fe) concentrations were diminished in fasted Group A wolves compared to fed Group B. Creatine phosphokinase (CPK) concentrations were elevated in fed Group A wolves. Serum creatinine (C) concentrations were reduced in both groups during feeding. Urinary urea: creatinine (U:C), potassium:creatine (K:C), and sodium:creatinine (Na:C, pooled Group A and B data) ratios decreased in fasted wolves. Differences were not found between fed and fasted wolves for mean corpuscular volume (MCV), serum cortisol, glucose, calcium (Ca), bilirubin, serum glutamate-oxaloacetate transaminase (SGOT), serum glutamate-pyruvate transaminase (SGOT), serum glutamate-pyruvate transaminase (SGPT), alkaline phosphatase, and luteinizing hormone (LH) concentrations, total iron binding capacity (TIBC), and urinary calcium: creatine (Ca:C) ratios. Analysis of multiple blood or urine samples collected from free-ranging wolves would be useful in enabling researches and managers to identify the nutritional status and general health of wolves over time.

  20. Effect of terminal accuracy requirements on temporal gaze-hand coordination during fast discrete and reciprocal pointings

    PubMed Central

    2011-01-01

    Background Rapid discrete goal-directed movements are characterized by a well known coordination pattern between the gaze and the hand displacements. The gaze always starts prior to the hand movement and reaches the target before hand velocity peak. Surprisingly, the effect of the target size on the temporal gaze-hand coordination has not been directly investigated. Moreover, goal-directed movements are often produced in a reciprocal rather than in a discrete manner. The objectives of this work were to assess the effect of the target size on temporal gaze-hand coordination during fast 1) discrete and 2) reciprocal pointings. Methods Subjects performed fast discrete (experiment 1) and reciprocal (experiment 2) pointings with an amplitude of 50 cm and four target diameters (7.6, 3.8, 1.9 and 0.95 cm) leading to indexes of difficulty (ID = log2[2A/D]) of 3.7, 4.7, 5.7 and 6.7 bits. Gaze and hand displacements were synchronously recorded. Temporal gaze-hand coordination parameters were compared between experiments (discrete and reciprocal pointings) and IDs using analyses of variance (ANOVAs). Results Data showed that the magnitude of the gaze-hand lead pattern was much higher for discrete than for reciprocal pointings. Moreover, while it was constant for discrete pointings, it decreased systematically with an increasing ID for reciprocal pointings because of the longer duration of gaze anchoring on target. Conclusion Overall, the temporal gaze-hand coordination analysis revealed that even for high IDs, fast reciprocal pointings could not be considered as a concatenation of discrete units. Moreover, our data clearly illustrate the smooth adaptation of temporal gaze-hand coordination to terminal accuracy requirements during fast reciprocal pointings. It will be interesting for further researches to investigate if the methodology used in the experiment 2 allows assessing the effect of sensori-motor deficits on gaze-hand coordination. PMID:21320315

  1. Use of biotin targeted methotrexate–human serum albumin conjugated nanoparticles to enhance methotrexate antitumor efficacy

    PubMed Central

    Taheri, Azade; Dinarvand, Rassoul; Nouri, Faranak Salman; Khorramizadeh, Mohammad Reza; Borougeni, Atefeh Taheri; Mansoori, Pooria; Atyabi, Fatemeh

    2011-01-01

    Biotin molecules could be used as suitable targeting moieties in targeted drug delivery systems against tumors. To develop a biotin targeted drug delivery system, we employed human serum albumin (HSA) as a carrier. Methotrexate (MTX) molecules were conjugated to HSA. MTX-HSA nanoparticles (MTX-HSA NPs) were prepared from these conjugates by cross-linking the HSA molecules. Biotin molecules were then conjugated on the surface of MTX-HSA NPs. The anticancer efficacy of biotin targeted MTX-HSA NPs was evaluated in mice bearing 4T1 breast carcinoma. A single dose of biotin targeted MTX-HSA NPs showed stronger in vivo antitumor activity than non-targeted MTX-HSA NPs and free MTX. By 7 days after treatment, average tumor volume in the biotin targeted MTX-HSA NPs-treated group decreased to 17.6% of the initial tumor volume when the number of attached biotin molecules on MTX-HSA-NPs was the highest. Average tumor volume in non-targeted MTX-HSA NPs-treated mice grew rapidly and reached 250.7% of the initial tumor volume. Biotin targeted MTX-HSA NPs increased the survival of tumor-bearing mice to 47.5 ± 0.71 days and increased their life span up to 216.7%. Mice treated with biotin targeted MTX-HSA NPs showed slight body weight loss (8%) 21 days after treatment, whereas non-targeted MTX-HSA NPs treatment at the same dose caused a body weight loss of 27.05% ± 3.1%. PMID:21931482

  2. Radioisotope Electric Propulsion for Fast Outer Planetary Orbiters

    NASA Technical Reports Server (NTRS)

    Oleson, Steven; Benson, Scott; Gefert, Leon; Patterson, Michael; Schreiber, Jeffrey

    2002-01-01

    Recent interest in outer planetary targets by the Office of Space Science has spurred the search for technology options to enable relatively quick missions to outer planetary targets. Several options are being explored including solar electric propelled stages combined with aerocapture at the target and nuclear electric propulsion. Another option uses radioisotope powered electric thrusters to reach the outer planets. Past work looked at using this technology to provide faster flybys. A better use for this technology is for outer planet orbiters. Combined with medium class launch vehicles and a new direct trajectory these small, sub-kilowatt ion thrusters and Stirling radioisotope generators were found to allow missions as fast as 5 to 12 years for objects from Saturn to Pluto, respectively. Key to the development is light spacecraft and science payload technologies.

  3. Tagged fast neutron beams En > 6 MeV

    NASA Astrophysics Data System (ADS)

    Favela, F.; Huerta, A.; Santa Rita, P.; Ramos, A. T.; de Lucio, O.; Andrade, E.; Acosta, L.; Ortiz, M. E.; Araujo, V.; Murillo, G.; Policroniades, R.; Varela, A.; Chávez, E.

    2015-07-01

    Controlled flux of neutrons are produced through the 14N(d,n)15O nuclear reaction. Deuteron beams (2-4 MeV) are delivered by the CN-Van de Graaff accelerator and directed with full intensity to our Nitrogen target at SUGAR (SUpersonic GAs jet taRget). Each neutron is electronically tagged by the detection of the associated15O. Its energy and direction are known and "beams" of fast monochromatic tagged neutrons (En> 6 MeV) are available for basic research and applied work. MONDE is a large area (158 × 63 cm2) plastic scintillating slab (5 cm thick), viewed by 16 PMTs from the sides. Fast neutrons (MeV) entering the detector will produce a recoiling proton that induces a light spark at the spot. Signals from the 16 detectors are processed to deduce the position of the spark. Time logic signals from both the 15O detector and MONDE are combined to deduce a time of flight (TOF) signal. Finally, the position information together with the TOF yields the full momentum vector of each detected neutron.

  4. Fast automatic delineation of cardiac volume of interest in MSCT images

    NASA Astrophysics Data System (ADS)

    Lorenz, Cristian; Lessick, Jonathan; Lavi, Guy; Bulow, Thomas; Renisch, Steffen

    2004-05-01

    Computed Tomography Angiography (CTA) is an emerging modality for assessing cardiac anatomy. The delineation of the cardiac volume of interest (VOI) is a pre-processing step for subsequent visualization or image processing. It serves the suppression of anatomic structures being not in the primary focus of the cardiac application, such as sternum, ribs, spinal column, descending aorta and pulmonary vasculature. These structures obliterate standard visualizations such as direct volume renderings or maximum intensity projections. In addition, outcome and performance of post-processing steps such as ventricle suppression, coronary artery segmentation or the detection of short and long axes of the heart can be improved. The structures being part of the cardiac VOI (coronary arteries and veins, myocardium, ventricles and atria) differ tremendously in appearance. In addition, there is no clear image feature associated with the contour (or better cut-surface) distinguishing between cardiac VOI and surrounding tissue making the automatic delineation of the cardiac VOI a difficult task. The presented approach locates in a first step chest wall and descending aorta in all image slices giving a rough estimate of the location of the heart. In a second step, a Fourier based active contour approach delineates slice-wise the border of the cardiac VOI. The algorithm has been evaluated on 41 multi-slice CT data-sets including cases with coronary stents and venous and arterial bypasses. The typical processing time amounts to 5-10s on a 1GHz P3 PC.

  5. Effects of Fasting During Ramadan Month on Cognitive Function in Muslim Athletes

    PubMed Central

    Tian, Ho-Heng; Aziz, Abdul-Rashid; Png, Weileen; Wahid, Mohamed Faizul; Yeo, Donald; Constance Png, Ai-Li

    2011-01-01

    Purpose Our study aimed to profile the effect of fasting during the Ramadan month on cognitive function in a group of healthy Muslim athletes. Methods Eighteen male athletes underwent computerized neuropsychological testing during (fasting) and after (non-fasting) Ramadan. Diet was standardized, and tests were performed at 0900h and 1600h to characterize potential time-of-day (TOD) interactions. Psychomotor function (processing speed), vigilance (visual attention), visual learning and memory, working memory (executive function), verbal learning and memory were examined. Capillary glucose, body temperature, urine specific gravity, and sleep volume were also recorded. Results Fasting effects were observed for psychomotor function (Cohen's d=1.3, P=0.01) and vigilance (d=0.6, P=0.004), with improved performance at 0900h during fasting; verbal learning and memory was poorer at 1600h (d=-0.8, P=0.03). A TOD effect was present for psychomotor function (d=-0.4, P<0.001), visual learning (d=-0.5, P=0.04), verbal learning and memory (d=-1.3, P=0.001), with poorer performances at 1600h. There was no significant fasting effect on visual learning and working memory. Conclusions Our results show that the effect of fasting on cognition is heterogeneous and domain-specific. Performance in functions requiring sustained rapid responses was better in the morning, declining in the late afternoon, whereas performance in non-speed dependent accuracy measures was more resilient. PMID:22375233

  6. Glioma targeting and blood-brain barrier penetration by dual-targeting doxorubincin liposomes.

    PubMed

    Gao, Jian-Qing; Lv, Qing; Li, Li-Ming; Tang, Xin-Jiang; Li, Fan-Zhu; Hu, Yu-Lan; Han, Min

    2013-07-01

    Effective chemotherapy for glioblastoma requires a carrier that can penetrate the blood-brain barrier (BBB) and subsequently target the glioma cells. Dual-targeting doxorubincin (Dox) liposomes were produced by conjugating liposomes with both folate (F) and transferrin (Tf), which were proven effective in penetrating the BBB and targeting tumors, respectively. The liposome was characterized by particle size, Dox entrapment efficiency, and in vitro release profile. Drug accumulation in cells, P-glycoprotein (P-gp) expression, and drug transport across the BBB in the dual-targeting liposome group were examined by using bEnd3 BBB models. In vivo studies demonstrated that the dual-targeting Dox liposomes could transport across the BBB and mainly distribute in the brain glioma. The anti-tumor effect of the dual-targeting liposome was also demonstrated by the increased survival time, decreased tumor volume, and results of both hematoxylin-eosin staining and terminal deoxynucleotidyl transferase dUTP nick end labeling analysis. The dual-targeting Dox liposome could improve the therapeutic efficacy of brain glioma and were less toxic than the Dox solution, showing a dual-targeting effect. These results indicate that this dual-targeting liposome can be used as a potential carrier for glioma chemotherapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Elasticity-based three dimensional ultrasound real-time volume rendering

    NASA Astrophysics Data System (ADS)

    Boctor, Emad M.; Matinfar, Mohammad; Ahmad, Omar; Rivaz, Hassan; Choti, Michael; Taylor, Russell H.

    2009-02-01

    Volumetric ultrasound imaging has not gained wide recognition, despite the availability of real-time 3D ultrasound scanners and the anticipated potential of 3D ultrasound imaging in diagnostic and interventional radiology. Their use, however, has been hindered by the lack of real-time visualization methods that are capable of producing high quality 3D rendering of the target/surface of interest. Volume rendering is a known visualization method, which can display clear surfaces out of the acquired volumetric data, and has an increasing number of applications utilizing CT and MRI data. The key element of any volume rendering pipeline is the ability to classify the target/surface of interest by setting an appropriate opacity function. Practical and successful real-time 3D ultrasound volume rendering can be achieved in Obstetrics and Angio applications where setting these opacity functions can be done rapidly, and reliably. Unfortunately, 3D ultrasound volume rendering of soft tissues is a challenging task due to the presence of significant amount of noise and speckle. Recently, several research groups have shown the feasibility of producing 3D elasticity volume from two consecutive 3D ultrasound scans. This report describes a novel volume rendering pipeline utilizing elasticity information. The basic idea is to compute B-mode voxel opacity from the rapidly calculated strain values, which can also be mixed with conventional gradient based opacity function. We have implemented the volume renderer using GPU unit, which gives an update rate of 40 volume/sec.

  8. Volumetric modulated arc therapy of head-and-neck cancer on a fast-rotating O-ring linac: Plan quality and delivery time comparison with a C-arm linac.

    PubMed

    Michiels, Steven; Poels, Kenneth; Crijns, Wouter; Delombaerde, Laurence; De Roover, Robin; Vanstraelen, Bianca; Haustermans, Karin; Nuyts, Sandra; Depuydt, Tom

    2018-05-05

    Linac improvements in gantry speed, leaf speed and dose rate may increase the time-efficiency of volumetric modulated arc therapy (VMAT) delivery. The plan quality achievable with faster VMAT however remains to be investigated. In this study, a fast-rotating O-ring linac with fast-moving leaves is compared with a C-arm linac in terms of plan quality and delivery time for VMAT of head-and-neck cancer (HNC). For 30 patients with HNC, treatment planning was performed using dual-arc (HA2) and triple-arc (HA3) VMAT on a Halcyon fast-rotating O-ring linac and using dual-arc VMAT on a TrueBeam C-arm linac (TB2). Target coverage metrics and complication probabilities were compared. Plan delivery was verified using 3%/3 mm gamma-index analysis of helical diode array measurements. Volumetric image acquisition and plan delivery times were compared. All studied VMAT-techniques fulfilled the target coverage objectives. D 2% to the boost volume was higher for HA2 (median 103.7%, 1st-3rd quartile [103.5%;104.0%]) and HA3 (103.2% [103.0%;103.7%)] than for TB2 (102.6% [102.3%;103.0%)], resulting in an increased boost target dose heterogeneity for HA2 and HA3. Complication probabilities were comparable between HA2 and TB2, while HA3 showed a xerostomia probability reduction (0.8% [0.2%;1.8%]) and dysphagia probability reduction (1.0% [0.2%;1.8%]) compared with TB2. Gamma-index agreement scores were never below 93.0% for HA2, HA3 and TB2. Volumetric imaging and plan delivery time was shorter for HA2 (1 m 24 s ± 1 s) and HA3 (1 m 54 s ± 1 s) than for TB2 (2 m 47 s ± 1 s). For VMAT of HNC, the fast-rotating O-ring linac at least maintains the plan quality of two arcs on a C-arm linac while reducing the image acquisition and plan delivery time. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Target volume definition for post prostatectomy radiotherapy: Do the consensus guidelines correctly define the inferior border of the CTV?

    PubMed

    Manji, Mo; Crook, Juanita; Schmid, Matt; Rajapakshe, Rasika

    2016-01-01

    We compare urethrogram delineation of the caudal aspect of the anastomosis to the recommended guidelines of post prostatectomy radiotherapy. Level one evidence has established the indications for, and importance of, adjuvant radiotherapy following radical prostatectomy. Several guidelines have recently addressed delineation of the prostate bed target volume including identification of the vesico-urethral anastomosis, taken as the first CT slice caudal to visible urine in the bladder neck. The inferior border of clinical target volume is then variably defined 5-12 mm below this anastomosis or 15 mm cranial to the penile bulb. Thirty-three patients who received adjuvant radiotherapy following radical prostatectomy were reviewed. All underwent planning CT with urethrogram. The authors (MM, JC) independently identified the CT slice caudal to the last slice showing urine in the bladder neck (called the CT Reference Slice), and measured the distance between this and the tip of the urethrogram cone. Five patients also had a diagnostic MRI at the time of CT planning to better visualize the anatomy. Sixty-six readings were obtained. The mean distance between the Bladder CT Reference Slice and the most cranial urethrogram contrast slice was 16.1 mm (MM 16.4 mm, JC 15.8 mm), range: 6.8-34.2 mm. The mean distance between the urethrogram tip and the ischial tuberosities was 19.9 mm (range 12.5-29.8 mm). The mean distance between the CT Reference Slice and the ischial tuberosities was 36.9 mm (range 28.3-52.4 mm). Guidelines for prostate bed radiation post prostatectomy have been developed after publication of the trials proving benefit of such treatment, and are thus untested. The anastomosis is a frequent site of local relapse but is variably defined by the existing guidelines, none of which take into account anatomic patient variation and all of which are at variance with urethrogram data. We recommend the use of planning urethrogram to better delineate the vesico

  10. A cargo inspection system based on pulsed fast neutron analysis (PFNA).

    PubMed

    Ipe, N E; Olsher, R; Ryge, P; Mrozack, J; Thieu, J

    2005-01-01

    A cargo inspection system based on pulsed fast neutron analysis (PFNA) is to be used at a border crossing to detect explosives and contraband hidden in trucks and cargo containers. Neutrons are produced by the interaction of deuterons in a deuterium target mounted on a moveable scan arm. The collimated pulsed fast neutron beam is used to determine the location and composition of objects in a cargo container. The neutrons produce secondary gamma rays that are characteristic of the object's elemental composition. The cargo inspection system building consists of an accelerator room and an inspection tunnel. The accelerator room is shielded and houses the injector, accelerator and the neutron production gas target. The inspection tunnel is partially shielded. The truck or container to be inspected will be moved through the inspection tunnel by a conveyor system. The facility and radiation source terms considered in the shielding design are described.

  11. Fast-ball sports experts depend on an inhibitory strategy to reprogram their movement timing.

    PubMed

    Nakamoto, Hiroki; Ikudome, Sachi; Yotani, Kengo; Maruyama, Atsuo; Mori, Shiro

    2013-07-01

    The purpose of our study was to clarify whether an inhibitory strategy is used for reprogramming of movement timing by experts in fast-ball sports when they correct their movement timing due to unexpected environmental changes. We evaluated the influence of disruption of inhibitory function of the right inferior frontal gyrus (rIFG) on reprogramming of movement timing of experts and non-experts in fast-ball sports. The task was to manually press a button to coincide with the arrival of a moving target. The target moved at a constant velocity, and its velocity was suddenly either increased or decreased in some trials. The task was performed either with or without transcranial magnetic stimulation (TMS), which was delivered to the region of the rIFG. Under velocity change conditions without TMS, the experts showed significantly smaller timing errors and a higher rate of reprogramming of movement timing than the non-experts. Moreover, TMS application during the task significantly diminished the expert group's performance, but not the control group, particularly in the condition where the target velocity decreases. These results suggest that experts use an inhibitory strategy for reprogramming of movement timing. In addition, the rIFG inhibitory function contributes to the superior movement correction of experts in fast-ball sports.

  12. Widely-targeted quantitative lipidomics methodology by supercritical fluid chromatography coupled with fast-scanning triple quadrupole mass spectrometry.

    PubMed

    Takeda, Hiroaki; Izumi, Yoshihiro; Takahashi, Masatomo; Paxton, Thanai; Tamura, Shohei; Koike, Tomonari; Yu, Ying; Kato, Noriko; Nagase, Katsutoshi; Shiomi, Masashi; Bamba, Takeshi

    2018-05-03

    Lipidomics, the mass spectrometry-based comprehensive analysis of lipids, has attracted attention as an analytical approach to provide novel insight into lipid metabolism and to search for biomarkers. However, an ideal method for both comprehensive and quantitative analysis of lipids has not been fully developed. Herein, we have proposed a practical methodology for widely-targeted quantitative lipidome analysis using supercritical fluid chromatography fast-scanning triple-quadrupole mass spectrometry (SFC/QqQMS) and theoretically calculated a comprehensive lipid multiple reaction monitoring (MRM) library. Lipid classes can be separated by SFC with a normal phase diethylamine-bonded silica column with high-resolution, high-throughput, and good repeatability. Structural isomers of phospholipids can be monitored by mass spectrometric separation with fatty acyl-based MRM transitions. SFC/QqQMS analysis with an internal standard-dilution method offers quantitative information for both lipid class and individual lipid molecular species in the same lipid class. Additionally, data acquired using this method has advantages including reduction of misidentification and acceleration of data analysis. Using the SFC/QqQMS system, alteration of plasma lipid levels in myocardial infarction-prone rabbits to the supplementation of eicosapentaenoic acid was first observed. Our developed SFC/QqQMS method represents a potentially useful tool for in-depth studies focused on complex lipid metabolism and biomarker discovery. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Target margins in radiotherapy of prostate cancer

    PubMed Central

    Bauman, Glenn

    2016-01-01

    We reviewed the literature on the use of margins in radiotherapy of patients with prostate cancer, focusing on different options for image guidance (IG) and technical issues. The search in PubMed database was limited to include studies that involved external beam radiotherapy of the intact prostate. Post-prostatectomy studies, brachytherapy and particle therapy were excluded. Each article was characterized according to the IG strategy used: positioning on external marks using room lasers, bone anatomy and soft tissue match, usage of fiducial markers, electromagnetic tracking and adapted delivery. A lack of uniformity in margin selection among institutions was evident from the review. In general, introduction of pre- and in-treatment IG was associated with smaller planning target volume (PTV) margins, but there was a lack of definitive experimental/clinical studies providing robust information on selection of exact PTV values. In addition, there is a lack of comparative research regarding the cost–benefit ratio of the different strategies: insertion of fiducial markers or electromagnetic transponders facilitates prostate gland localization but at a price of invasive procedure; frequent pre-treatment imaging increases patient in-room time, dose and labour; online plan adaptation should improve radiation delivery accuracy but requires fast and precise computation. Finally, optimal protocols for quality assurance procedures need to be established. PMID:27377353

  14. Identifying factors associated with fast food consumption among adolescents in Beijing China using a theory-based approach.

    PubMed

    Ma, R; Castellanos, D C; Bachman, J

    2016-07-01

    China is in the midst of the nutrition transition with increasing rates of obesity and dietary changes. One contributor is the increase in fast food chains within the country. The purpose of this study was to develop a theory-based instrument that explores influencing factors of fast food consumption in adolescents residing in Beijing, China. Cross-sectional study. Value expectancy and theory of planned behaviour were utilised to explore influencing factors of fast food consumption in the target population. There were 201 Chinese adolescents between the ages of 12 and 18. Cronbach's alpha correlation coefficients were used to examine internal reliability of the theory-based questionnaire. Bivariate correlations and a MANOVA were utilised to determine the relationship between theory-based constructs, body mass index (BMI)-for-age and fast food intake frequency as well as to determine differences in theory-based scores among fast food consumption frequency groupings. The theory-based questionnaire showed good reliability. Furthermore, there was a significant difference in the theory-based subcategory scores between fast food frequency groups. A significant positive correlation was observed between times per week fast food was consumed and each theory-based subscale score. Using BMI-for-age of 176 participants, 81% were normal weight and 19% were considered overweight or obese. Results showed consumption of fast food to be on average 1.50 ± 1.33 per week. The relationship between BMI-for-age and times per week fast food was consumed was not significant. As the nutrition transition continues and fast food chains expand, it is important to explore factors effecting fast food consumption in China. Interventions targeting influencing factors can be developed to encourage healthy dietary choice in the midst of this transition. Copyright © 2016. Published by Elsevier Ltd.

  15. The role of PET in target localization for radiotherapy treatment planning.

    PubMed

    Rembielak, Agata; Price, Pat

    2008-02-01

    Positron emission tomography (PET) is currently accepted as an important tool in oncology, mostly for diagnosis, staging and restaging purposes. It provides a new type of information in radiotherapy, functional rather than anatomical. PET imaging can also be used for target volume definition in radiotherapy treatment planning. The need for very precise target volume delineation has arisen with the increasing use of sophisticated three-dimensional conformal radiotherapy techniques and intensity modulated radiation therapy. It is expected that better delineation of the target volume may lead to a significant reduction in the irradiated volume, thus lowering the risk of treatment complications (smaller safety margins). Better tumour visualisation also allows a higher dose of radiation to be applied to the tumour, which may lead to better tumour control. The aim of this article is to review the possible use of PET imaging in the radiotherapy of various cancers. We focus mainly on non-small cell lung cancer, lymphoma and oesophageal cancer, but also include current opinion on the use of PET-based planning in other tumours including brain, uterine cervix, rectum and prostate.

  16. Therapeutic analysis of high-dose-rate {sup 192}Ir vaginal cuff brachytherapy for endometrial cancer using a cylindrical target volume model and varied cancer cell distributions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Hualin, E-mail: hualin.zhang@northwestern.edu; Donnelly, Eric D.; Strauss, Jonathan B.

    Purpose: To evaluate high-dose-rate (HDR) vaginal cuff brachytherapy (VCBT) in the treatment of endometrial cancer in a cylindrical target volume with either a varied or a constant cancer cell distributions using the linear quadratic (LQ) model. Methods: A Monte Carlo (MC) technique was used to calculate the 3D dose distribution of HDR VCBT over a variety of cylinder diameters and treatment lengths. A treatment planning system (TPS) was used to make plans for the various cylinder diameters, treatment lengths, and prescriptions using the clinical protocol. The dwell times obtained from the TPS were fed into MC. The LQ model wasmore » used to evaluate the therapeutic outcome of two brachytherapy regimens prescribed either at 0.5 cm depth (5.5 Gy × 4 fractions) or at the vaginal mucosal surface (8.8 Gy × 4 fractions) for the treatment of endometrial cancer. An experimentally determined endometrial cancer cell distribution, which showed a varied and resembled a half-Gaussian distribution, was used in radiobiology modeling. The equivalent uniform dose (EUD) to cancer cells was calculated for each treatment scenario. The therapeutic ratio (TR) was defined by comparing VCBT with a uniform dose radiotherapy plan in term of normal cell survival at the same level of cancer cell killing. Calculations of clinical impact were run twice assuming two different types of cancer cell density distributions in the cylindrical target volume: (1) a half-Gaussian or (2) a uniform distribution. Results: EUDs were weakly dependent on cylinder size, treatment length, and the prescription depth, but strongly dependent on the cancer cell distribution. TRs were strongly dependent on the cylinder size, treatment length, types of the cancer cell distributions, and the sensitivity of normal tissue. With a half-Gaussian distribution of cancer cells which populated at the vaginal mucosa the most, the EUDs were between 6.9 Gy × 4 and 7.8 Gy × 4, the TRs were in the range from (5.0){sup 4} to

  17. Generation of Parametric Equivalent-Area Targets for Design of Low-Boom Supersonic Concepts

    NASA Technical Reports Server (NTRS)

    Li, Wu; Shields, Elwood

    2011-01-01

    A tool with an Excel visual interface is developed to generate equivalent-area (A(sub e)) targets that satisfy the volume constraints for a low-boom supersonic configuration. The new parametric Ae target explorer allows users to interactively study the tradeoffs between the aircraft volume constraints and the low-boom characteristics (e.g., loudness) of the ground signature. Moreover, numerical optimization can be used to generate the optimal A(sub e) target for given A(sub e) volume constraints. A case study is used to demonstrate how a generated low-boom Ae target can be matched by a supersonic configuration that includes a fuselage, wing, nacelle, pylon, aft pod, horizontal tail, and vertical tail. The low-boom configuration is verified by sonic-boom analysis with an off-body pressure distribution at three body lengths below the configuration

  18. FAST Mapping of Diffuse HI Gas in the Local Universe

    NASA Astrophysics Data System (ADS)

    Zhu, M.; Pisano, D. J.; Ai, M.; Jiao, Q.

    2016-02-01

    We propose to use the Five hundred meter Aperture Spherical radio Telescope (FAST) to map the diffuse intergalactic HI gas in the local universe at column densities of NHI=1018 cm-2 and below. The major science goal is to study gas accretion during galaxy evolution, and trace cosmic web features in the local universe. We disuss the technical feasibilty of such a deep survey, and have conducted test observations with the Arecibo 305 m telescope. Our preliminary results shows that, with about a few thousand hours of observing time, FAST will be able to map several hundred square degree regions at 1 σ of NHI=2×1017 cm-2 level out to a distance of 5-10 Mpc, and with a volume 1000 larger than that of the Local Group.

  19. The p14 FAST Protein of Reptilian Reovirus Increases Vesicular Stomatitis Virus Neuropathogenesis▿

    PubMed Central

    Brown, Christopher W.; Stephenson, Kyle B.; Hanson, Stephen; Kucharczyk, Michael; Duncan, Roy; Bell, John C.; Lichty, Brian D.

    2009-01-01

    The fusogenic orthoreoviruses express nonstructural fusion-associated small transmembrane (FAST) proteins that induce cell-cell fusion and syncytium formation. It has been speculated that the FAST proteins may serve as virulence factors by promoting virus dissemination and increased or altered cytopathology. To directly test this hypothesis, the gene encoding the p14 FAST protein of reptilian reovirus was inserted into the genome of a heterologous virus that does not naturally form syncytia, vesicular stomatitis virus (VSV). Expression of the p14 FAST protein by the VSV/FAST recombinant gave the virus a highly fusogenic phenotype in cell culture. The growth of this recombinant fusogenic VSV strain was unaltered in vitro but was significantly enhanced in vivo. The VSV/FAST recombinant consistently generated higher titers of virus in the brains of BALB/c mice after intranasal or intravenous infection compared to the parental VSV/green fluorescent protein (GFP) strain that expresses GFP in place of p14. The VSV/FAST recombinant also resulted in an increased incidence of hind-limb paralysis, it infected a larger volume of brain tissue, and it induced more extensive neuropathology, thus leading to a lower maximum tolerable dose than that for the VSV/GFP parental virus. In contrast, an interferon-inducing mutant of VSV expressing p14 was still attenuated, indicating that this interferon-inducing phenotype is dominant to the fusogenic properties conveyed by the FAST protein. Based on this evidence, we conclude that the reovirus p14 FAST protein can function as a bona fide virulence factor. PMID:18971262

  20. Fast and robust segmentation of the striatum using deep convolutional neural networks.

    PubMed

    Choi, Hongyoon; Jin, Kyong Hwan

    2016-12-01

    Automated segmentation of brain structures is an important task in structural and functional image analysis. We developed a fast and accurate method for the striatum segmentation using deep convolutional neural networks (CNN). T1 magnetic resonance (MR) images were used for our CNN-based segmentation, which require neither image feature extraction nor nonlinear transformation. We employed two serial CNN, Global and Local CNN: The Global CNN determined approximate locations of the striatum. It performed a regression of input MR images fitted to smoothed segmentation maps of the striatum. From the output volume of Global CNN, cropped MR volumes which included the striatum were extracted. The cropped MR volumes and the output volumes of Global CNN were used for inputs of Local CNN. Local CNN predicted the accurate label of all voxels. Segmentation results were compared with a widely used segmentation method, FreeSurfer. Our method showed higher Dice Similarity Coefficient (DSC) (0.893±0.017 vs. 0.786±0.015) and precision score (0.905±0.018 vs. 0.690±0.022) than FreeSurfer-based striatum segmentation (p=0.06). Our approach was also tested using another independent dataset, which showed high DSC (0.826±0.038) comparable with that of FreeSurfer. Comparison with existing method Segmentation performance of our proposed method was comparable with that of FreeSurfer. The running time of our approach was approximately three seconds. We suggested a fast and accurate deep CNN-based segmentation for small brain structures which can be widely applied to brain image analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Synthetic aperture radar image formation for the moving-target and near-field bistatic cases

    NASA Astrophysics Data System (ADS)

    Ding, Yu

    This dissertation addresses topics in two areas of synthetic aperture radar (SAR) image formation: time-frequency based SAR imaging of moving targets and a fast backprojection (BP) algorithm for near-field bistatic SAR imaging. SAR imaging of a moving target is a challenging task due to unknown motion of the target. We approach this problem in a theoretical way, by analyzing the Wigner-Ville distribution (WVD) based SAR imaging technique. We derive approximate closed-form expressions for the point-target response of the SAR imaging system, which quantify the image resolution, and show how the blurring in conventional SAR imaging can be eliminated, while the target shift still remains. Our analyses lead to accurate prediction of the target position in the reconstructed images. The derived expressions also enable us to further study additional aspects of WVD-based SAR imaging. Bistatic SAR imaging is more involved than the monostatic SAR case, because of the separation of the transmitter and the receiver, and possibly the changing bistatic geometry. For near-field bistatic SAR imaging, we develop a novel fast BP algorithm, motivated by a newly proposed fast BP algorithm in computer tomography. First we show that the BP algorithm is the spatial-domain counterpart of the benchmark o -- k algorithm in bistatic SAR imaging, yet it avoids the frequency-domain interpolation in the o -- k algorithm, which may cause artifacts in the reconstructed image. We then derive the band-limited property for BP methods in both monostatic and bistatic SAR imaging, which is the basis for developing the fast BP algorithm. We compare our algorithm with other frequency-domain based algorithms, and show that it achieves better reconstructed image quality, while having the same computational complexity as that of the frequency-domain based algorithms.

  2. UCx target preparations and characterizations

    NASA Astrophysics Data System (ADS)

    Andrighetto, Alberto; Corradetti, Stefano; Manzolaro, Mattia; Scarpa, Daniele; Monetti, Alberto; Rossignoli, Massimo; Borgna, Francesca; Ballan, Michele; Agostini, Mattia; D'Agostini, Fabio; Ferrari, Matteo; Zenoni, Aldo

    2018-05-01

    The Target-Ion Source unit is the core of an ISOL-RIB facility. Many international ISOL facilities have chosen different layouts of this unit. Many research groups are involved in research and development of targets capable of dissipating high power and, at the same time, be able to have a fast isotope release. This is mandatory in order to produce beams of short half-life isotopes. The research of new materials with advanced microstructural features is crucial in this field. The design of a proper target is indeed strictly related to the obtainment of porous refractory materials, which are capable to work under extreme conditions (temperatures up to 2000 °C in high vacuum) with a high release efficiency. For SPES, the second generation Italian ISOL-RIB Facility, the target will be made of uranium carbide (UCx) in which, by fission induced by a proton beam of 40 MeV of energy (8 kW of power), isotopes in the 60-160 amu mass region are produced. The current technological developments are also crucial in the study of third generation ISOL facilities.

  3. Fast decomposition of two ultrasound longitudinal waves in cancellous bone using a phase rotation parameter for bone quality assessment: Simulation study.

    PubMed

    Taki, Hirofumi; Nagatani, Yoshiki; Matsukawa, Mami; Kanai, Hiroshi; Izumi, Shin-Ichi

    2017-10-01

    Ultrasound signals that pass through cancellous bone may be considered to consist of two longitudinal waves, which are called fast and slow waves. Accurate decomposition of these fast and slow waves is considered to be highly beneficial in determination of the characteristics of cancellous bone. In the present study, a fast decomposition method using a wave transfer function with a phase rotation parameter was applied to received signals that have passed through bovine bone specimens with various bone volume to total volume (BV/TV) ratios in a simulation study, where the elastic finite-difference time-domain method is used and the ultrasound wave propagated parallel to the bone axes. The proposed method succeeded to decompose both fast and slow waves accurately; the normalized residual intensity was less than -19.5 dB when the specimen thickness ranged from 4 to 7 mm and the BV/TV value ranged from 0.144 to 0.226. There was a strong relationship between the phase rotation value and the BV/TV value. The ratio of the peak envelope amplitude of the decomposed fast wave to that of the slow wave increased monotonically with increasing BV/TV ratio, indicating the high performance of the proposed method in estimation of the BV/TV value in cancellous bone.

  4. SMV⊥: Simplex of maximal volume based upon the Gram-Schmidt process

    NASA Astrophysics Data System (ADS)

    Salazar-Vazquez, Jairo; Mendez-Vazquez, Andres

    2015-10-01

    In recent years, different algorithms for Hyperspectral Image (HI) analysis have been introduced. The high spectral resolution of these images allows to develop different algorithms for target detection, material mapping, and material identification for applications in Agriculture, Security and Defense, Industry, etc. Therefore, from the computer science's point of view, there is fertile field of research for improving and developing algorithms in HI analysis. In some applications, the spectral pixels of a HI can be classified using laboratory spectral signatures. Nevertheless, for many others, there is no enough available prior information or spectral signatures, making any analysis a difficult task. One of the most popular algorithms for the HI analysis is the N-FINDR because it is easy to understand and provides a way to unmix the original HI in the respective material compositions. The N-FINDR is computationally expensive and its performance depends on a random initialization process. This paper proposes a novel idea to reduce the complexity of the N-FINDR by implementing a bottom-up approach based in an observation from linear algebra and the use of the Gram-Schmidt process. Therefore, the Simplex of Maximal Volume Perpendicular (SMV⊥) algorithm is proposed for fast endmember extraction in hyperspectral imagery. This novel algorithm has complexity O(n) with respect to the number of pixels. In addition, the evidence shows that SMV⊥ calculates a bigger volume, and has lower computational time complexity than other poular algorithms on synthetic and real scenarios.

  5. Proton emission from cone-in-shell fast-ignition experiments at Omega

    NASA Astrophysics Data System (ADS)

    Sinenian, N.; Theobald, W.; Frenje, J. A.; Stoeckl, C.; Séguin, F. H.; Li, C. K.; Petrasso, R. D.; Stephens, R. B.

    2012-11-01

    Measurements of energetic protons from cone-in-shell fast-igniton implosions at Omega have been conducted. In these experiments, charged-particle spectrometers were used to measure a significant population (>1013) of energetic protons (7.5 MeV max.), indicating the presence of strong electric fields. These energetic protons, observed in directions both transverse and forward relative to the direction of the short-pulse laser beam, have been used to study aspects of coupling efficiency of the petawatt fast-ignitior beam. Approximately 5% of the laser energy coupled to hot electrons was lost to fast ions. Forward going protons were less energetic and showed no dependence on laser intensity or whether the cone tip was intact when the short-pulse laser was fired. Maximum energies of protons emitted transverse to the cone-in-shell target scale with incident on-target laser intensity (2-6×1018W-cm-2), as described by the ponderomotive scaling (∝I1/2). It is shown that these protons are accelerated from the entire cone, rather than from the cone tip alone. These protons were used to estimate the lower limit on the hot-electron temperature, which was found to be hotter than the ponderomotive scaling by factors of 2-3.

  6. Patterns-of-failure guided biological target volume definition for head and neck cancer patients: FDG-PET and dosimetric analysis of dose escalation candidate subregions.

    PubMed

    Mohamed, Abdallah S R; Cardenas, Carlos E; Garden, Adam S; Awan, Musaddiq J; Rock, Crosby D; Westergaard, Sarah A; Brandon Gunn, G; Belal, Abdelaziz M; El-Gowily, Ahmed G; Lai, Stephen Y; Rosenthal, David I; Fuller, Clifton D; Aristophanous, Michalis

    2017-08-01

    To identify the radio-resistant subvolumes in pretreatment FDG-PET by mapping the spatial location of the origin of tumor recurrence after IMRT for head-and-neck squamous cell cancer to the pretreatment FDG-PET/CT. Patients with local/regional recurrence after IMRT with available FDG-PET/CT and post-failure CT were included. For each patient, both pre-therapy PET/CT and recurrence CT were co-registered with the planning CT (pCT). A 4-mm radius was added to the centroid of mapped recurrence growth target volumes (rGTV's) to create recurrence nidus-volumes (NVs). The overlap between boost-tumor-volumes (BTV) representing different SUV thresholds/margins combinations and NVs was measured. Forty-seven patients were eligible. Forty-two (89.4%) had type A central high dose failure. Twenty-six (48%) of type A rGTVs were at the primary site and 28 (52%) were at the nodal site. The mean dose of type A rGTVs was 71Gy. BTV consisting of 50% of the maximum SUV plus 10mm margin was the best subvolume for dose boosting due to high coverage of primary site NVs (92.3%), low average relative volume to CTV1 (41%), and least average percent voxels outside CTV1 (19%). The majority of loco-regional recurrences originate in the regions of central-high-dose. When correlated with pretreatment FDG-PET, the majority of recurrences originated in an area that would be covered by additional 10mm margin on the volume of 50% of the maximum FDG uptake. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Theory of the stopping power of fast multicharged ions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yudin, G.L.

    1991-12-01

    The processes of Coulomb excitation and ionization of atoms by a fast charged particle moving along a classical trajectory are studied. The target electrons are described by the Dirac equation, while the field of the incident particle is described by the Lienard-Wiechert potential. The theory is formulated in the form most convenient for investigation of various characteristics of semiclassical atomic collisions. The theory of sudden perturbations, which is valid at high enough velocities for a high projectile charge, is employed to obtain probabilities and cross sections of the Coulomb excitation and ionization of atomic hydrogen by fast multiply charged ions.more » Based on the semiclassical sudden Born approximation, the ionization cross section and the average electronic energy loss of a fast ion in a single collision with an atom are investigated over a wide specific energy range from 500 keV/amu to 50 MeV/amu.« less

  8. Pragmatics & Language Learning. Volume 12

    ERIC Educational Resources Information Center

    Kasper, Gabriele, Ed.; Nguyen, Hanh thi, Ed.; Yoshimi, Dina Rudolph, Ed.; Yoshioka, Jim K., Ed.

    2010-01-01

    This volume examines the organization of second language and multilingual speakers' talk and pragmatic knowledge across a range of naturalistic and experimental activities. Based on data collected on Danish, English, Hawai'i Creole, Indonesian, and Japanese as target languages, the contributions explore the nexus of pragmatic knowledge,…

  9. Studies on cryogenic Xe capillary jet target for laser-produced plasma EUV-light source

    NASA Astrophysics Data System (ADS)

    Inoue, T.; Nica, P. E.; Kaku, K.; Shimoura, A.; Amano, S.; Miyamoto, S.; Mochizuki, T.

    2006-03-01

    In this paper, characterizations of a cryogenic Xe capillary jet target for a laser-produced plasma extreme ultraviolet (EUV) light source are reported. The capillary jet target is a candidate of fast-supplying targets for mitigating debris generation and target consumption in a vacuum chamber without reducing the EUV conversion efficiency. Xe capillary jets (jet velocity ~ 0.4 m/s) were generated in vacuum by using annular nozzles chilled to ~ 170 K at a Xe backing pressure of ~ 0.7 MPa. Forming mechanisms of the capillary jet targets were studied by using numerical calculations. Furthermore, laser-produced plasma EUV generation was performed by irradiating a Nd:YAG laser (1064 nm, ~ 0.5 J, 10 ns, 120 μmφ, ~ 4×10 11 W/cm2) on a Xe capillary jet target (outer / inner diameter = 100 / 70 μmφ). The angular distribution of EUV generation was approximately uniform around the Xe capillary jet target, and the peak kinetic energy of the fast-ions was evaluated to be ~ 2 keV.

  10. Muslim patients' expectations and attitudes about Ramadan fasting during pregnancy.

    PubMed

    Lou, Alina; Hammoud, Maya

    2016-03-01

    To investigate Muslim women's attitudes concerning Ramadan fasting during pregnancy and determine how healthcare providers can better serve this population. A cross-sectional study targeted Muslim patients with active obstetric records within the University of Michigan Health System who received care at clinics in metro Detroit (MI, USA) during Ramadan in 2013. Patients aged 18-50 years were approached between July 7 and August 15, and asked to complete a written survey on perceptions of fasting, influences on decision making, and healthcare expectations. Among the 37 women who completed the survey, 26 (70%) did not fast in their current or most recent pregnancy during Ramadan. Overall, 23 (62%) women believed that fasting was harmful to themselves, their fetus, or both. Seven (19%) women reported consulting others about fasting during pregnancy, with the most influential individuals being Muslim scholars, followed by family/relatives and healthcare providers. The most important characteristics desired in a physician included being respectful of Islamic beliefs and possessing knowledge about Ramadan. Most women chose not to fast during pregnancy. Although few consulted healthcare providers, pregnant Muslim women valued their opinions. Healthcare providers need to educate themselves about which topics to discuss with Muslim patients to provide care on an individual basis. Copyright © 2015 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  11. Low-dose fixed-target serial synchrotron crystallography.

    PubMed

    Owen, Robin L; Axford, Danny; Sherrell, Darren A; Kuo, Anling; Ernst, Oliver P; Schulz, Eike C; Miller, R J Dwayne; Mueller-Werkmeister, Henrike M

    2017-04-01

    The development of serial crystallography has been driven by the sample requirements imposed by X-ray free-electron lasers. Serial techniques are now being exploited at synchrotrons. Using a fixed-target approach to high-throughput serial sampling, it is demonstrated that high-quality data can be collected from myoglobin crystals, allowing room-temperature, low-dose structure determination. The combination of fixed-target arrays and a fast, accurate translation system allows high-throughput serial data collection at high hit rates and with low sample consumption.

  12. Treat-to-target trials in diabetes.

    PubMed

    Wangnoo, Subhash K; Sethi, Bipin; Sahay, Rakesh K; John, Mathew; Ghosal, Samit; Sharma, Surendra K

    2014-03-01

    Treat-to-target is a therapeutic concept that considers well defined and specific physiologic targets as aims in controlling the pathophysiology of the disease. It has been widely used in diseases that pathophysiology includes, chronic metabolic and physiological disturbances, namely rheumatic conditions, vascular medicine and diabetes. In diabetes, the availability of "gold-standard" quantitative measures like fasting plasma glucose and glycated hemoglobin make the application of treat-to-target trials especially pertinent. Treatment modalities which have used single therapeutic agents or combinations or in combination with a variety of titration algorithms and implementation protocols have broadened our understanding of diabetes management with specific reference to insulin initiation and maintenance. Treat-to-target trials have been used to investigate a wide variety of questions including efficacy, safety, effect of treatment on comorbidities and patient satisfaction, ideal mechanisms to implement insulin initiation etc. A more generalized acceptance and implementation of treat-to-target trials may finally revolutionize diabetes management by combining aspects of individual care with standard treatment protocols.

  13. Is a Clinical Target Volume (CTV) Necessary in the Treatment of Lung Cancer in the Modern Era Combining 4-D Imaging and Image-guided Radiotherapy (IGRT)?

    PubMed

    Kilburn, Jeremy M; Lucas, John T; Soike, Michael H; Ayala-Peacock, Diandra N; Blackstock, Arthur W; Hinson, William H; Munley, Michael T; Petty, William J; Urbanic, James J

    2016-01-23

    We hypothesized that omission of clinical target volumes (CTV) in lung cancer radiotherapy would not compromise control by determining retrospectively if the addition of a CTV would encompass the site of failure. Stage II-III patients were treated from 2009-2012 with daily cone-beam imaging and a 5 mm planning target volume (PTV) without a CTV. PTVs were expanded 1 cm and termed CTVretro. Recurrences were scored as 1) within the PTV, 2) within CTVretro, or 3) outside the PTV. Locoregional control (LRC), distant control (DC), progression-free survival (PFS), and overall survival (OS) were estimated. Among 110 patients, Stage IIIA 57%, IIIB 32%, IIA 4%, and IIB 7%. Eighty-six percent of Stage III patients received chemotherapy. Median dose was 70 Gy (45-74 Gy) and fraction size ranged from 1.5-2.7 Gy. Median follow-up was 12 months, median OS was 22 months (95% CI 19-30 months), and LRC at two years was 69%. Fourteen local and eight regional events were scored with two CTVretro failures equating to a two-year CTV failure-free survival of 98%. Omission of a 1 cm CTV expansion appears feasible based on only two events among 110 patients and should be considered in radiation planning.

  14. Definition of the key target volume in radiosurgical management of arteriovenous malformations: a new dynamic concept based on angiographic circulation time.

    PubMed

    Valle, Ramiro Del; Zenteno, Marco; Jaramillo, José; Lee, Angel; De Anda, Salvador

    2008-12-01

    The cumulative experience worldwide indicates complete radiosurgical obliteration rates of brain arteriovenous malformations (AVMs) ranging from 35 to 90%. The purpose of this study was to propose a strategy to increase the obliteration rate for AVMs through the dynamic definition of the key target volume (KTV). A prospective series of patients harboring an AVM was assessed using digital subtraction angiography in which a digital counter was used to measure the several stages of the frame-by-frame circulation time. All the patients were analyzed using dynamic measurement planning to define the KTV, corresponding to the volume of the shunt with the least vascular resistance and the earliest venous drainage. All patients underwent catheter-based angiography, a subgroup was additionally assessed by means of a superselective catheterization, and among these a further subgroup received embolization. The shunts were also categorized according to their angioarchitectural type: fistulous, plexiform, or mixed. The authors applied the radiosurgery-based grading system (RBGS) as well to find a correlation with the obliteration rate. This series includes 44 patients treated by radiosurgery; global angiography was performed for all patients, including dynamic measurement planning. Eighty-four percent of them underwent superselective catheterization, and 50% of the total population underwent embolization. In the embolized arm of the study, the pretreatment volume was up to 120 ml. In patients with a single treatment, the mean volume was 8.5 ml, and the median volume was 6.95 +/- 4.56 ml (mean +/- standard deviation), with a KTV of up to 15 ml. For prospectively staged radiosurgery, the mean KTV was 28 ml. The marginal radiation dose was 18-22 Gy, with a mean of dose 20 Gy. The mean RBGS score was 1.70. The overall obliteration rate was 91%, including the repeated radiosurgery group (4 patients), in which 100% showed complete obliteration. The overall permanent deficit was 2 of

  15. Feasibility of the Precise Energy Calibration for Fast Neutron Spectrometers

    NASA Astrophysics Data System (ADS)

    Gaganov, V. V.; Usenko, P. L.; Kryzhanovskaja, M. A.

    2017-12-01

    Computational studies aimed at improving the accuracy of measurements performed using neutron generators with a tritium target were performed. A measurement design yielding an extremely narrow peak in the energy spectrum of DT neutrons was found. The presence of such a peak establishes the conditions for precise energy calibration of fast-neutron spectrometers.

  16. TargetNet: a web service for predicting potential drug-target interaction profiling via multi-target SAR models.

    PubMed

    Yao, Zhi-Jiang; Dong, Jie; Che, Yu-Jing; Zhu, Min-Feng; Wen, Ming; Wang, Ning-Ning; Wang, Shan; Lu, Ai-Ping; Cao, Dong-Sheng

    2016-05-01

    Drug-target interactions (DTIs) are central to current drug discovery processes and public health fields. Analyzing the DTI profiling of the drugs helps to infer drug indications, adverse drug reactions, drug-drug interactions, and drug mode of actions. Therefore, it is of high importance to reliably and fast predict DTI profiling of the drugs on a genome-scale level. Here, we develop the TargetNet server, which can make real-time DTI predictions based only on molecular structures, following the spirit of multi-target SAR methodology. Naïve Bayes models together with various molecular fingerprints were employed to construct prediction models. Ensemble learning from these fingerprints was also provided to improve the prediction ability. When the user submits a molecule, the server will predict the activity of the user's molecule across 623 human proteins by the established high quality SAR model, thus generating a DTI profiling that can be used as a feature vector of chemicals for wide applications. The 623 SAR models related to 623 human proteins were strictly evaluated and validated by several model validation strategies, resulting in the AUC scores of 75-100 %. We applied the generated DTI profiling to successfully predict potential targets, toxicity classification, drug-drug interactions, and drug mode of action, which sufficiently demonstrated the wide application value of the potential DTI profiling. The TargetNet webserver is designed based on the Django framework in Python, and is freely accessible at http://targetnet.scbdd.com .

  17. TargetNet: a web service for predicting potential drug-target interaction profiling via multi-target SAR models

    NASA Astrophysics Data System (ADS)

    Yao, Zhi-Jiang; Dong, Jie; Che, Yu-Jing; Zhu, Min-Feng; Wen, Ming; Wang, Ning-Ning; Wang, Shan; Lu, Ai-Ping; Cao, Dong-Sheng

    2016-05-01

    Drug-target interactions (DTIs) are central to current drug discovery processes and public health fields. Analyzing the DTI profiling of the drugs helps to infer drug indications, adverse drug reactions, drug-drug interactions, and drug mode of actions. Therefore, it is of high importance to reliably and fast predict DTI profiling of the drugs on a genome-scale level. Here, we develop the TargetNet server, which can make real-time DTI predictions based only on molecular structures, following the spirit of multi-target SAR methodology. Naïve Bayes models together with various molecular fingerprints were employed to construct prediction models. Ensemble learning from these fingerprints was also provided to improve the prediction ability. When the user submits a molecule, the server will predict the activity of the user's molecule across 623 human proteins by the established high quality SAR model, thus generating a DTI profiling that can be used as a feature vector of chemicals for wide applications. The 623 SAR models related to 623 human proteins were strictly evaluated and validated by several model validation strategies, resulting in the AUC scores of 75-100 %. We applied the generated DTI profiling to successfully predict potential targets, toxicity classification, drug-drug interactions, and drug mode of action, which sufficiently demonstrated the wide application value of the potential DTI profiling. The TargetNet webserver is designed based on the Django framework in Python, and is freely accessible at http://targetnet.scbdd.com.

  18. Correlates of Sugar-Sweetened Beverages Purchased for Children at Fast-Food Restaurants.

    PubMed

    Cantor, Jonathan; Breck, Andrew; Elbel, Brian

    2016-11-01

    To determine consumer and fast-food purchase characteristics associated with the purchase of a sugar-sweetened beverage, as well as calories and grams of sugar, for children at a fast-food restaurant. We completed cross-sectional analyses of fast-food restaurant receipts and point-of-purchase surveys (n = 483) collected during 2013 and 2014 in New York City and Newark and Jersey City, New Jersey. Caregivers purchased beverages for half of all children in our sample. Approximately 60% of these beverages were sugar-sweetened beverages. Fast-food meals with sugar-sweetened beverages had, on average, 179 more calories than meals with non-sugar-sweetened beverages. Being an adolescent or male, having a caregiver with a high school degree or less, having a caregiver who saw the posted calorie information, ordering a combination meal, and eating the meal in the restaurant were associated with ordering a sugar-sweetened beverage. Purchases that included a combination meal or were consumed in the restaurant included more beverage grams of sugar and calories. Characteristics of fast-food purchases appear to have the largest and most important association to beverage calories for children at fast-food restaurants. Targeting fast-food restaurants, particularly combination meals, may improve childhood obesity rates.

  19. Correlates of Sugar-Sweetened Beverages Purchased for Children at Fast-Food Restaurants

    PubMed Central

    Cantor, Jonathan; Breck, Andrew

    2016-01-01

    Objectives. To determine consumer and fast-food purchase characteristics associated with the purchase of a sugar-sweetened beverage, as well as calories and grams of sugar, for children at a fast-food restaurant. Methods. We completed cross-sectional analyses of fast-food restaurant receipts and point-of-purchase surveys (n = 483) collected during 2013 and 2014 in New York City and Newark and Jersey City, New Jersey. Results. Caregivers purchased beverages for half of all children in our sample. Approximately 60% of these beverages were sugar-sweetened beverages. Fast-food meals with sugar-sweetened beverages had, on average, 179 more calories than meals with non–sugar-sweetened beverages. Being an adolescent or male, having a caregiver with a high school degree or less, having a caregiver who saw the posted calorie information, ordering a combination meal, and eating the meal in the restaurant were associated with ordering a sugar-sweetened beverage. Purchases that included a combination meal or were consumed in the restaurant included more beverage grams of sugar and calories. Conclusions. Characteristics of fast-food purchases appear to have the largest and most important association to beverage calories for children at fast-food restaurants. Targeting fast-food restaurants, particularly combination meals, may improve childhood obesity rates. PMID:27715306

  20. Bistability: Requirements on Cell-Volume, Protein Diffusion, and Thermodynamics

    PubMed Central

    Endres, Robert G.

    2015-01-01

    Bistability is considered wide-spread among bacteria and eukaryotic cells, useful e.g. for enzyme induction, bet hedging, and epigenetic switching. However, this phenomenon has mostly been described with deterministic dynamic or well-mixed stochastic models. Here, we map known biological bistable systems onto the well-characterized biochemical Schlögl model, using analytical calculations and stochastic spatiotemporal simulations. In addition to network architecture and strong thermodynamic driving away from equilibrium, we show that bistability requires fine-tuning towards small cell volumes (or compartments) and fast protein diffusion (well mixing). Bistability is thus fragile and hence may be restricted to small bacteria and eukaryotic nuclei, with switching triggered by volume changes during the cell cycle. For large volumes, single cells generally loose their ability for bistable switching and instead undergo a first-order phase transition. PMID:25874711

  1. Merchantable Volume and Weights of Mahoe in Puerto Rican Plantations

    Treesearch

    John K. Francis

    1989-01-01

    Mahoe (Hibiscus elatus Sw.), a fast-growing tree whose wood is considered valuable, is planted and managed primarily in the West Indies. Until now, volume and weight tables have not been available for the species. Data used in this paper were collected from 50 felled trees in a range of sizes from plantations across Puerto Rico. Using linear...

  2. Target volume geometric change and/or deviation from the cranium during fractionated stereotactic radiotherapy for brain metastases: potential pitfalls in image guidance based on bony anatomy alignment.

    PubMed

    Ohtakara, Kazuhiro; Hoshi, Hiroaki

    2014-12-01

    This study sought to evaluate the potential geometrical change and/or displacement of the target relative to the cranium during fractionated stereotactic radiotherapy (FSRT) for treating newly developed brain metastases. For 16 patients with 21 lesions treated with image-guided frameless FSRT in 5 or 10 fractions using a 6-degree-of-freedom image guidance system-integrated platform, the unenhanced computed tomography or T2-weighted magnetic resonance images acquired until the completion of FSRT were fused to the planning image datasets for comparison. Significant change was defined as ≥3-mm change in the tumour diameter or displacement of the tumour centroid. FSRT was started 1 day after planning image acquisition. Tumour shrinkage, deviation and both were observed in 2, 1 and 1 of the 21 lesions, respectively, over a period of 7-13 days. Tumour shrinkage or deviation resulted in an increase or decrease in the marginal dose to the tumour, respectively, and a substantial increase in the irradiated volume for the surrounding tissue irrespective of the pattern of alteration. No obvious differences in the clinical and treatment characteristics were noted among the populations with or without significant changes in tumour volume or position. Target deformity and/or deviation can unexpectedly occur even during relatively short-course FSRT, inevitably leading to a gradual discrepancy between the planned and actually delivered doses to the tumour and surrounding tissue. To appropriately weigh the treatment outcome against the planned dose distribution, target deformity and/or deviation should also be considered in addition to the immobilisation accuracy, as image guidance with bony anatomy alignment does not necessarily guarantee accurate target localisation until completion of FSRT. © 2014 The Royal Australian and New Zealand College of Radiologists.

  3. Target-mediated drug disposition model for drugs with two binding sites that bind to a target with one binding site.

    PubMed

    Gibiansky, Leonid; Gibiansky, Ekaterina

    2017-10-01

    The paper extended the TMDD model to drugs with two identical binding sites (2-1 TMDD). The quasi-steady-state (2-1 QSS), quasi-equilibrium (2-1 QE), irreversible binding (2-1 IB), and Michaelis-Menten (2-1 MM) approximations of the model were derived. Using simulations, the 2-1 QSS approximation was compared with the full 2-1 TMDD model. As expected and similarly to the standard TMDD for monoclonal antibodies (mAb), 2-1 QSS predictions were nearly identical to 2-1 TMDD predictions, except for times of fast changes following initiation of dosing, when equilibrium has not yet been reached. To illustrate properties of new equations and approximations, several variations of population PK data for mAbs with soluble (slow elimination of the complex) or membrane-bound (fast elimination of the complex) targets were simulated from a full 2-1 TMDD model and fitted to 2-1 TMDD models, to its approximations, and to the standard (1-1) QSS model. For a mAb with a soluble target, it was demonstrated that the 2-1 QSS model provided nearly identical description of the observed (simulated) free drug and total target concentrations, although there was some minor bias in predictions of unobserved free target concentrations. The standard QSS approximation also provided a good description of the observed data, but was not able to distinguish between free drug concentrations (with no target attached and both binding site free) and partially bound drug concentrations (with one of the binding sites occupied by the target). For a mAb with a membrane-bound target, the 2-1 MM approximation adequately described the data. The 2-1 QSS approximation converged 10 times faster than the full 2-1 TMDD, and its run time was comparable with the standard QSS model.

  4. Target coverage in image-guided stereotactic body radiotherapy of liver tumors.

    PubMed

    Wunderink, Wouter; Méndez Romero, Alejandra; Vásquez Osorio, Eliana M; de Boer, Hans C J; Brandwijk, René P; Levendag, Peter C; Heijmen, Ben J M

    2007-05-01

    To determine the effect of image-guided procedures (with computed tomography [CT] and electronic portal images before each treatment fraction) on target coverage in stereotactic body radiotherapy for liver patients using a stereotactic body frame (SBF) and abdominal compression. CT guidance was used to correct for day-to-day variations in the tumor's mean position in the SBF. By retrospectively evaluating 57 treatment sessions, tumor coverage, as obtained with the clinically applied CT-guided protocol, was compared with that of alternative procedures. The internal target volume-plus (ITV(+)) was introduced to explicitly include uncertainties in tumor delineations resulting from CT-imaging artifacts caused by residual respiratory motion. Tumor coverage was defined as the volume overlap of the ITV(+), derived from a tumor delineated in a treatment CT scan, and the planning target volume. Patient stability in the SBF, after acquisition of the treatment CT scan, was evaluated by measuring the displacement of the bony anatomy in the electronic portal images relative to CT. Application of our clinical protocol (with setup corrections following from manual measurements of the distances between the contours of the planning target volume and the daily clinical target volume in three orthogonal planes, multiple two-dimensional) increased the frequency of nearly full (> or = 99%) ITV(+) coverage to 77% compared with 63% without setup correction. An automated three-dimensional method further improved the frequency to 96%. Patient displacements in the SBF were generally small (< or = 2 mm, 1 standard deviation), but large craniocaudal displacements (maximal 7.2 mm) were occasionally observed. Daily, CT-assisted patient setup may substantially improve tumor coverage, especially with the automated three-dimensional procedure. In the present treatment design, patient stability in the SBF should be verified with portal imaging.

  5. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    DOEpatents

    Thode, Lester E.

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

  6. Generation of ultra-high-pressure shocks by collision of a fast plasma projectile driven in the laser-induced cavity pressure acceleration scheme with a solid target

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Badziak, J.; Rosiński, M.; Krousky, E.

    2015-03-15

    A novel, efficient method of generating ultra-high-pressure shocks is proposed and investigated. In this method, the shock is generated by collision of a fast plasma projectile (a macro-particle) driven by laser-induced cavity pressure acceleration (LICPA) with a solid target placed at the LICPA accelerator channel exit. Using the measurements performed at the kilojoule PALS laser facility and two-dimensional hydrodynamic simulations, it is shown that the shock pressure ∼ Gbar can be produced with this method at the laser driver energy of only a few hundred joules, by an order of magnitude lower than the energy needed for production of suchmore » pressure with other laser-based methods known so far.« less

  7. Left ventricle: fully automated segmentation based on spatiotemporal continuity and myocardium information in cine cardiac magnetic resonance imaging (LV-FAST).

    PubMed

    Wang, Lijia; Pei, Mengchao; Codella, Noel C F; Kochar, Minisha; Weinsaft, Jonathan W; Li, Jianqi; Prince, Martin R; Wang, Yi

    2015-01-01

    CMR quantification of LV chamber volumes typically and manually defines the basal-most LV, which adds processing time and user-dependence. This study developed an LV segmentation method that is fully automated based on the spatiotemporal continuity of the LV (LV-FAST). An iteratively decreasing threshold region growing approach was used first from the midventricle to the apex, until the LV area and shape discontinued, and then from midventricle to the base, until less than 50% of the myocardium circumference was observable. Region growth was constrained by LV spatiotemporal continuity to improve robustness of apical and basal segmentations. The LV-FAST method was compared with manual tracing on cardiac cine MRI data of 45 consecutive patients. Of the 45 patients, LV-FAST and manual selection identified the same apical slices at both ED and ES and the same basal slices at both ED and ES in 38, 38, 38, and 41 cases, respectively, and their measurements agreed within -1.6 ± 8.7 mL, -1.4 ± 7.8 mL, and 1.0 ± 5.8% for EDV, ESV, and EF, respectively. LV-FAST allowed LV volume-time course quantitatively measured within 3 seconds on a standard desktop computer, which is fast and accurate for processing the cine volumetric cardiac MRI data, and enables LV filling course quantification over the cardiac cycle.

  8. Sea ice classification using fast learning neural networks

    NASA Technical Reports Server (NTRS)

    Dawson, M. S.; Fung, A. K.; Manry, M. T.

    1992-01-01

    A first learning neural network approach to the classification of sea ice is presented. The fast learning (FL) neural network and a multilayer perceptron (MLP) trained with backpropagation learning (BP network) were tested on simulated data sets based on the known dominant scattering characteristics of the target class. Four classes were used in the data simulation: open water, thick lossy saline ice, thin saline ice, and multiyear ice. The BP network was unable to consistently converge to less than 25 percent error while the FL method yielded an average error of approximately 1 percent on the first iteration of training. The fast learning method presented can significantly reduce the CPU time necessary to train a neural network as well as consistently yield higher classification accuracy than BP networks.

  9. The SPES High Power ISOL production target

    NASA Astrophysics Data System (ADS)

    Andrighetto, A.; Corradetti, S.; Ballan, M.; Borgna, F.; Manzolaro, M.; Scarpa, D.; Monetti, A.; Rossignoli, M.; Silingardi, R.; Mozzi, A.; Vivian, G.; Boratto, E.; De Ruvo, L.; Sattin, N.; Meneghetti, G.; Oboe, R.; Guerzoni, M.; Margotti, A.; Ferrari, M.; Zenoni, A.; Prete, G.

    2016-11-01

    SPES (Selective Production of Exotic Species) is a facility under construction at INFN-LNL (Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Legnaro), aimed to produce intense neutron-rich radioactive ion beams (RIBs). These will be obtained using the ISOL (Isotope Separation On-Line) method, bombarding a uranium carbide target with a proton beam of 40MeV energy and currents up to 200μA. The target configuration was designed to obtain a high number of fissions, up to 1013 per second, low power deposition and fast release of the produced isotopes. The exotic isotopes generated in the target are ionized, mass separated and re-accelerated by the ALPI superconducting LINAC at energies of 10AMeV and higher, for masses in the region of A = 130 amu , with an expected rate on the secondary target up to 109 particles per second. In this work, recent results on the R&D activities regarding the SPES RIB production target-ion source system are reported.

  10. Ultrasound assessment of gastric volume in children after drinking carbohydrate-containing fluids.

    PubMed

    Song, I-K; Kim, H-J; Lee, J-H; Kim, E-H; Kim, J-T; Kim, H-S

    2016-04-01

    Gastric ultrasound is a valid tool for non-invasive assessment of the nature and volume of gastric contents in adults and children. Perioperative fasting guidelines recommend oral carbohydrates up to 2 h before elective surgery. We evaluated gastric volume in children using ultrasound before and after drinking carbohydrate fluids before surgery. Paediatric patients younger than 18 yr old undergoing elective surgery were enrolled. Initial ultrasound assessment of gastric volume was performed after fasting for 8 h. Two hours before surgery, patients were given carbohydrate drinks: 15 ml kg(-1) for patients younger than 3 yr old and 10 ml kg(-1) for those more than 3 yr old. Before induction of general anaesthesia, the gastric volume was reassessed. Parental satisfaction scores (0=totally satisfied, 10=totally dissatisfied) and complications were recorded. Of the 86 enrolled patients, 79 completed the study; three refused to ingest the requested volume, and surgery was delayed for more than 2 h in four patients. The mean (sd) of the initial and second ultrasound measurements were 2.09 (0.97) and 1.85 (0.94) cm(2), respectively (P=0.01; mean difference 0.24 cm(2), 95% confidence interval 0.06-0.43). The median (interquartile range) satisfaction score was 2.4 (0-6). Two instances of postoperative vomiting and one instance of postoperative nausea occurred. Carbohydrate fluids ingested 2 h before surgery reduced the gastric volume and did not cause serious complications in paediatric patients. Parents were satisfied with the preoperative carbohydrate drink. Children may benefit from drinking carbohydrate fluids up to 2 h before elective surgery. cris.nih.go.kr (KCT0001546). © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Real-Time Robust Tracking for Motion Blur and Fast Motion via Correlation Filters

    PubMed Central

    Xu, Lingyun; Luo, Haibo; Hui, Bin; Chang, Zheng

    2016-01-01

    Visual tracking has extensive applications in intelligent monitoring and guidance systems. Among state-of-the-art tracking algorithms, Correlation Filter methods perform favorably in robustness, accuracy and speed. However, it also has shortcomings when dealing with pervasive target scale variation, motion blur and fast motion. In this paper we proposed a new real-time robust scheme based on Kernelized Correlation Filter (KCF) to significantly improve performance on motion blur and fast motion. By fusing KCF and STC trackers, our algorithm also solve the estimation of scale variation in many scenarios. We theoretically analyze the problem for CFs towards motions and utilize the point sharpness function of the target patch to evaluate the motion state of target. Then we set up an efficient scheme to handle the motion and scale variation without much time consuming. Our algorithm preserves the properties of KCF besides the ability to handle special scenarios. In the end extensive experimental results on benchmark of VOT datasets show our algorithm performs advantageously competed with the top-rank trackers. PMID:27618046

  12. Real-Time Robust Tracking for Motion Blur and Fast Motion via Correlation Filters.

    PubMed

    Xu, Lingyun; Luo, Haibo; Hui, Bin; Chang, Zheng

    2016-09-07

    Visual tracking has extensive applications in intelligent monitoring and guidance systems. Among state-of-the-art tracking algorithms, Correlation Filter methods perform favorably in robustness, accuracy and speed. However, it also has shortcomings when dealing with pervasive target scale variation, motion blur and fast motion. In this paper we proposed a new real-time robust scheme based on Kernelized Correlation Filter (KCF) to significantly improve performance on motion blur and fast motion. By fusing KCF and STC trackers, our algorithm also solve the estimation of scale variation in many scenarios. We theoretically analyze the problem for CFs towards motions and utilize the point sharpness function of the target patch to evaluate the motion state of target. Then we set up an efficient scheme to handle the motion and scale variation without much time consuming. Our algorithm preserves the properties of KCF besides the ability to handle special scenarios. In the end extensive experimental results on benchmark of VOT datasets show our algorithm performs advantageously competed with the top-rank trackers.

  13. Variability of the volume and thickness of sea ice in the Bay of Bothnia

    NASA Astrophysics Data System (ADS)

    Ronkainen, Iina; Lehtiranta, Jonni; Lensu, Mikko; Rinne, Eero; Hordoir, Robinson; Haapala, Jari

    2017-04-01

    Variability of the volume and thickness of sea ice in the Bay of Bothnia In our study, we want to quantify the variability of sea ice volume and thickness in the Bay of Bothnia and to introduce the drivers of the observed variability. There has been similar studies, but only for fast ice. We use various different data sets: in-situ ice thickness data, remote sensing data, model data and ice charts. In-situ data is from the regular monitoring stations in the coastal fast ice zone and from field campaigns. The remote sensing data is helicopter-borne and ship-borne electromagnetic data. The models we use are HELMI and NEMO-Nordic. We analyze the different data sets and compare them to each other to solve the inter-annual variability and to discuss the ratio of level and deformed ice.

  14. Real-time detection of fast and thermal neutrons in radiotherapy with CMOS sensors.

    PubMed

    Arbor, Nicolas; Higueret, Stephane; Elazhar, Halima; Combe, Rodolphe; Meyer, Philippe; Dehaynin, Nicolas; Taupin, Florence; Husson, Daniel

    2017-03-07

    The peripheral dose distribution is a growing concern for the improvement of new external radiation modalities. Secondary particles, especially photo-neutrons produced by the accelerator, irradiate the patient more than tens of centimeters away from the tumor volume. However the out-of-field dose is still not estimated accurately by the treatment planning softwares. This study demonstrates the possibility of using a specially designed CMOS sensor for fast and thermal neutron monitoring in radiotherapy. The 14 microns-thick sensitive layer and the integrated electronic chain of the CMOS are particularly suitable for real-time measurements in γ/n mixed fields. An experimental field size dependency of the fast neutron production rate, supported by Monte Carlo simulations and CR-39 data, has been observed. This dependency points out the potential benefits of a real-time monitoring of fast and thermal neutron during beam intensity modulated radiation therapies.

  15. SECOND TARGET STATION MODERATOR PERFORMANCE WITH A ROTATING TARGET

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Remec, Igor; Gallmeier, Franz X; Rennich, Mark J

    2016-01-01

    Oak Ridge National Laboratory manages and operates the Spallation Neutron Source and the High Flux Isotope Reactor, two of the world's most advanced neutron scattering facilities. Both facilities are funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Science, and are available to researchers from all over the world. Delivering cutting edge science requires continuous improvements and development of the facilities and instruments. The SNS was designed from the outset to accommodate an additional target station, or Second Target Station (STS), and an upgraded accelerator feeding proton beams to STS and the existing First Targetmore » Station (FTS). Upgrade of the accelerator and the design and construction of STS are being proposed. The presently considered STS configuration is driven with short (<1 s) proton pulses at 10 Hz repetition rate and 467 kW proton beam power, and is optimized for high intensity and high resolution long wavelength neutron applications. STS will allow installation of 22 beamlines and will expand and complement the current national neutron scattering capabilities. In 2015 the STS studies were performed for a compact tungsten target; first a stationary tungsten plate target was analyzed to considerable details and then dropped in favor of a rotating target. For both target options the proton beam footprint as small as acceptable from mechanical and heat removal aspects is required to arrive at a compact-volume neutron production zone in the target, which is essential for tight coupling of target and moderators and for achieving high-intensity peak neutron fluxes. This paper will present recent STS work with the emphasis on neutronics and moderator performance.« less

  16. Fast Conformal Thermal Ablation in the Prostate with Transurethral Multi-Sectored Ultrasound Devices and MR Guidance

    NASA Astrophysics Data System (ADS)

    Kinsey, Adam M.; Diederich, Chris J.; Nau, William H.; Ross, Anthony B.; Pauly, Kim Butts; Rieke, Viola; Sommer, Graham

    2007-05-01

    Transurethral ultrasound applicators incorporating an array of multisectored tubular transducers were evaluated in theoretical simulations and in vivo canine prostates under MR guidance as a method for fast, conformal thermal therapy of the prostate. Comprehensive simulations with a biothermal model investigated the effect on lesion creation of sector size, perfusion, treatment time, rectal cooling, prostate target dimensions, and feedback controller parameters (maximum temperature, pilot points at boundary, update times). In vivo canine prostates (n = 4) were treated with trisectored ultrasound transducers (3 mm OD) under MR temperature monitoring to contour the ablation zone (>52 C for 1-2 min) to the boundary of the prostate. Contiguous thermal lesions extended 2 cm in radius from the urethra in less than 15 min and independent sector control simultaneously allowed for conformal treatment in the angular dimension. Experiments investigated sequential translation of the transducer assembly within the catheter for tailoring heat treatments to different partitions in the prostate (base, apex) without changing the initial setup. This treatment method offered greater lesion shape control in three dimensions and slightly lengthened the overall treatment time. The MR temperature images correlated with post-treatment histology and accurately controlled the heating to the target boundary. MR-based control of transurethral ultrasound devices appeared more practical with multisectored transducers compared to rotating curvilinear and planar applicators due to less stringent requirements on spatial and temporal MR parameters. This study demonstrated the applicability of these devices in the prostate for anterior-lateral BPH treatment, and whole gland or quadrant target volumes for cancer treatment.

  17. Set-up uncertainties: online correction with X-ray volume imaging.

    PubMed

    Kataria, Tejinder; Abhishek, Ashu; Chadha, Pranav; Nandigam, Janardhan

    2011-01-01

    To determine interfractional three-dimensional set-up errors using X-ray volumetric imaging (XVI). Between December 2007 and August 2009, 125 patients were taken up for image-guided radiotherapy using online XVI. After matching of reference and acquired volume view images, set-up errors in three translation directions were recorded and corrected online before treatment each day. Mean displacements, population systematic (Σ), and random (σ) errors were calculated and analyzed using SPSS (v16) software. Optimum clinical target volume (CTV) to planning target volume (PTV) margin was calculated using Van Herk's (2.5Σ + 0.7 σ) and Stroom's (2Σ + 0.7 σ) formula. Patients were grouped in 4 cohorts, namely brain, head and neck, thorax, and abdomen-pelvis. The mean vector displacement recorded were 0.18 cm, 0.15 cm, 0.36 cm, and 0.35 cm for brain, head and neck, thorax, and abdomen-pelvis, respectively. Analysis of individual mean set-up errors revealed good agreement with the proposed 0.3 cm isotropic margins for brain and 0.5 cm isotropic margins for head-neck. Similarly, 0.5 cm circumferential and 1 cm craniocaudal proposed margins were in agreement with thorax and abdomen-pelvic cases. The calculated mean displacements were well within CTV-PTV margin estimates of Van Herk (90% population coverage to minimum 95% prescribed dose) and Stroom (99% target volume coverage by 95% prescribed dose). Employing these individualized margins in a particular cohort ensure comparable target coverage as described in literature, which is further improved if XVI-aided set-up error detection and correction is used before treatment.

  18. Draft Site Treatment Plan (DSTP), Volumes I and II

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    D`Amelio, J.

    1994-08-30

    Site Treatment Plans (STP) are required for facilities at which the DOE generates or stores mixed waste. This Draft Site Treatment Plan (DSTP) the second step in a three-phase process, identifies the currently preferred options for treating mixed waste at the Savannah River Site (SRS) or for developing treatment technologies where technologies do not exist or need modification. The DSTP reflects site-specific preferred options, developed with the state`s input and based on existing available information. To the extent possible, the DSTP identifies specific treatment facilities for treating the mixed waste and proposes schedules. Where the selection of specific treatment facilitiesmore » is not possible, schedules for alternative activities such as waste characterization and technology assessment are provided. All schedule and cost information presented is preliminary and is subject to change. The DSTP is comprised of two volumes: this Compliance Plan Volume and the Background Volume. This Compliance Plan Volume proposes overall schedules with target dates for achieving compliance with the land disposal restrictions (LDR) of RCRA and procedures for converting the target dates into milestones to be enforced under the Order. The more detailed discussion of the options contained in the Background Volume is provided for informational purposes only.« less

  19. Influence of large hiatus hernia on cardiac volumes. A prospective observational cohort study by cardiovascular magnetic resonance.

    PubMed

    Milito, Pamela; Lombardi, Massimo; Asti, Emanuele; Bonitta, Gianluca; Fina, Dario; Bandera, Francesco; Bonavina, Luigi

    2018-05-09

    Large hiatus hernia (LHH) is often associated with post-prandial dyspnea, palpitations or chest discomfort, but its effect on cardiac volumes and performance is still debated. Before and 3-months after laparoscopic repair, 35 patients underwent cardiovascular magnetic resonance (CMR) in the fasting state and after a standardized meal. Preoperatively, LHH size increased significantly after meal (p < 0.010). Compared to the fasting state, a systematic trend of volume reduction of the cardiac chambers was observed. In addition, both the left ventricle stroke volume (p = 0.012) and the ejection fraction (p = 0.010) were significantly reduced. At 3-months after surgery there was a statistically significant increase in left atrial volume (p = 0.029), overall left ventricle volume (p < 0.05) and right ventricle end-systolic volume (p = 0.046). Both FEV 1 (Forced expiratory volume) (p = 0.02) and FVC (Forced Vital Capacity) (p = 0.01) values significantly improved after surgery. Cardiorespiratory symptoms significantly improved compared to pre-operative values (p < 0.01). The global heart function was significantly impaired by a standardized meal in the presence of a LHH. Restoration of the cardiac physiological status and improvement of clinical symptoms were noted after surgery. A multidisciplinary evaluation and CMR with a challenge meal may be added to routine pre-operative testing to select symptomatic patients for surgical hernia repair. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Time history solution program, L225 (TEV126). Volume 1: Engineering and usage

    NASA Technical Reports Server (NTRS)

    Kroll, R. I.; Tornallyay, A.; Clemmons, R. E.

    1979-01-01

    Volume 1 of a two volume document is presented. The usage of the convolution program L225 (TEV 126) is described. The program calculates the time response of a linear system by convoluting the impulsive response function with the time-dependent excitation function. The convolution is performed as a multiplication in the frequency domain. Fast Fourier transform techniques are used to transform the product back into the time domain to obtain response time histories. A brief description of the analysis used is presented.

  1. FAST User Guide

    NASA Technical Reports Server (NTRS)

    Walatka, Pamela P.; Clucas, Jean; McCabe, R. Kevin; Plessel, Todd; Potter, R.; Cooper, D. M. (Technical Monitor)

    1994-01-01

    The Flow Analysis Software Toolkit, FAST, is a software environment for visualizing data. FAST is a collection of separate programs (modules) that run simultaneously and allow the user to examine the results of numerical and experimental simulations. The user can load data files, perform calculations on the data, visualize the results of these calculations, construct scenes of 3D graphical objects, and plot, animate and record the scenes. Computational Fluid Dynamics (CFD) visualization is the primary intended use of FAST, but FAST can also assist in the analysis of other types of data. FAST combines the capabilities of such programs as PLOT3D, RIP, SURF, and GAS into one environment with modules that share data. Sharing data between modules eliminates the drudgery of transferring data between programs. All the modules in the FAST environment have a consistent, highly interactive graphical user interface. Most commands are entered by pointing and'clicking. The modular construction of FAST makes it flexible and extensible. The environment can be custom configured and new modules can be developed and added as needed. The following modules have been developed for FAST: VIEWER, FILE IO, CALCULATOR, SURFER, TOPOLOGY, PLOTTER, TITLER, TRACER, ARCGRAPH, GQ, SURFERU, SHOTET, and ISOLEVU. A utility is also included to make the inclusion of user defined modules in the FAST environment easy. The VIEWER module is the central control for the FAST environment. From VIEWER, the user can-change object attributes, interactively position objects in three-dimensional space, define and save scenes, create animations, spawn new FAST modules, add additional view windows, and save and execute command scripts. The FAST User Guide uses text and FAST MAPS (graphical representations of the entire user interface) to guide the user through the use of FAST. Chapters include: Maps, Overview, Tips, Getting Started Tutorial, a separate chapter for each module, file formats, and system

  2. [Evaluation of the learning curve of residents in localizing a phantom target with ultrasonography].

    PubMed

    Dessieux, T; Estebe, J-P; Bloc, S; Mercadal, L; Ecoffey, C

    2008-10-01

    Few information are available regarding the learning curve in ultrasonography and even less for ultrasound-guided regional anesthesia. This study aimed to evaluate in a training program the learning curve on a phantom of 12 residents novice in ultrasonography. Twelve trainees inexperienced in ultrasonography were given introductory training consisting of didactic formation on the various components of the portable ultrasound machine (i.e. on/off button, gain, depth, resolution, and image storage). Then, students performed three trials, in two sets of increased difficulty, at executing these predefined tasks: adjustments of the machine, then localization of a small plastic piece introduced into roasting pork (3 cm below the surface). At the end of the evaluation, the residents were asked to insert a 22 G needle into an exact predetermined target (i.e. point of fascia intersection). The progression of the needle was continuously controlled by ultrasound visualization using injection of a small volume of water (needle perpendicular to the longitudinal plane of the ultrasound beam). Two groups of two different examiners evaluated for each three trials the skill of the residents (quality, time to perform the machine adjustments, to localize the plastic target, and to hydrolocalize, and volume used for hydrolocalization). After each trial, residents evaluated their performance using a difficulty scale (0: easy to 10: difficult). All residents performed the adjustments from the last trial of each set, with a learning curve observed in terms of duration. Localization of the plastic piece was achieved by all residents at the 6th trial, with a shorter duration of localization. Hydrolocalization was achieved after the 4th trial by all subjects. Difficulty scale was correlated to the number of trials. All these results were independent of the experience of residents in regional anesthesia. Four trials were necessary to adjust correctly the machine, to localize a target, and to

  3. Anomalously Fast Diffusion of Targeted Carbon Nanotubes in Cellular Spheroids.

    PubMed

    Wang, Yichun; Bahng, Joong Hwan; Che, Quantong; Han, Jishu; Kotov, Nicholas A

    2015-08-25

    Understanding transport of carbon nanotubes (CNTs) and other nanocarriers within tissues is essential for biomedical imaging and drug delivery using these carriers. Compared to traditional cell cultures in animal studies, three-dimensional tissue replicas approach the complexity of the actual organs and enable high temporal and spatial resolution of the carrier permeation. We investigated diffusional transport of CNTs in highly uniform spheroids of hepatocellular carcinoma and found that apparent diffusion coefficients of CNTs in these tissue replicas are anomalously high and comparable to diffusion rates of similarly charged molecules with molecular weights 10000× lower. Moreover, diffusivity of CNTs in tissues is enhanced after functionalization with transforming growth factor β1. This unexpected trend contradicts predictions of the Stokes-Einstein equation and previously obtained empirical dependences of diffusivity on molecular mass for permeants in gas, liquid, solid or gel. It is attributed to the planar diffusion (gliding) of CNTs along cellular membranes reducing effective dimensionality of diffusional space. These findings indicate that nanotubes and potentially similar nanostructures are capable of fast and deep permeation into the tissue, which is often difficult to realize with anticancer agents.

  4. Progress on inert matrix fuels for minor actinide transmutation in fast reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bonnerot, Jean-Marc; Ferroud-Plattet, Marie-Pierre; Lamontagne, Jerome

    2007-07-01

    An extensive irradiation program has been devoted by CEA to the assessment of transmutation using minor actinide bearing inert support targets. A first irradiation experiment was performed in the fast neutron reactor Phenix, in parallel to other experiments carried out in the HFR and Siloe reactors, in order to assess the behavior under fast neutron flux of various materials intended as inert support matrix for transmutation targets. This experiment, which included the two steps MATINA 1 and MATINA 1A, was completed in 2004 and underwent complete post irradiation examinations (PIE) , whose results are presented in this paper. All themore » pure inert materials showed a satisfactory behavior under fast neutrons except Al{sub 2}O{sub 3} - which exhibits a swelling close to 11 vol. % after irradiation. In presence of UO{sub 2} fissile particles, MgAl{sub 2}O{sub 4} proved to be more stable in term of swelling as inert support than MgO and Al{sub 2}O{sub 3} matrices, under the same irradiation conditions. A second experiment ECRIX H in Phenix involving composite pellets with an MgO matrix and AmO{sub 2-x} particles was completed in 2006. The very first PIE results on ECRIX H are described in this paper. At the light of these first experiments, a second phase dedicated to the design optimization of the target was initiated and three new irradiation experiments - MATINA 2-3, CAMIX COCHIX in Phenix and HELIOS in HFR - were started in 2006 and 2007. (authors)« less

  5. Accurate, consistent, and fast droplet splitting and dispensing in electrowetting on dielectric digital microfluidics

    NASA Astrophysics Data System (ADS)

    Nikapitiya, N. Y. Jagath B.; Nahar, Mun Mun; Moon, Hyejin

    2017-12-01

    This letter reports two novel electrode design considerations to satisfy two very important aspects of EWOD operation—(1) Highly consistent volume of generated droplets and (2) Highly improved accuracy in the generated droplet volume. Considering the design principles investigated two novel designs were proposed; L-junction electrode design to offer high throughput droplet generation and Y-junction electrode design to split a droplet very fast while maintaining equal volume of each part. Devices of novel designs were fabricated and tested, and the results are compared with those of conventional approach. It is demonstrated that inaccuracy and inconsistency of droplet volume dispensed in the device with novel electrode designs are as low as 0.17 and 0.10%, respectively, while those of conventional approach are 25 and 0.76%, respectively. The dispensing frequency is enhanced from 4 to 9 Hz by using the novel design.

  6. Targeted alpha therapy using short-lived alpha-particles and the promise of nanobodies as targeting vehicle

    PubMed Central

    Dekempeneer, Yana; Keyaerts, Marleen; Krasniqi, Ahmet; Puttemans, Janik; Muyldermans, Serge; Lahoutte, Tony; D’huyvetter, Matthias; Devoogdt, Nick

    2016-01-01

    ABSTRACT Introduction: The combination of a targeted biomolecule that specifically defines the target and a radionuclide that delivers a cytotoxic payload offers a specific way to destroy cancer cells. Targeted radionuclide therapy (TRNT) aims to deliver cytotoxic radiation to cancer cells and causes minimal toxicity to surrounding healthy tissues. Recent advances using α-particle radiation emphasizes their potential to generate radiation in a highly localized and toxic manner because of their high level of ionization and short range in tissue. Areas covered: We review the importance of targeted alpha therapy (TAT) and focus on nanobodies as potential beneficial vehicles. In recent years, nanobodies have been evaluated intensively as unique antigen-specific vehicles for molecular imaging and TRNT. Expert opinion: We expect that the efficient targeting capacity and fast clearance of nanobodies offer a high potential for TAT. More particularly, we argue that the nanobodies’ pharmacokinetic properties match perfectly with the interesting decay properties of the short-lived α-particle emitting radionuclides Astatine-211 and Bismuth-213 and offer an interesting treatment option particularly for micrometastatic cancer and residual disease. PMID:27145158

  7. Neighborhood fast food restaurants and fast food consumption: A national study

    PubMed Central

    2011-01-01

    Background Recent studies suggest that neighborhood fast food restaurant availability is related to greater obesity, yet few studies have investigated whether neighborhood fast food restaurant availability promotes fast food consumption. Our aim was to estimate the effect of neighborhood fast food availability on frequency of fast food consumption in a national sample of young adults, a population at high risk for obesity. Methods We used national data from U.S. young adults enrolled in wave III (2001-02; ages 18-28) of the National Longitudinal Study of Adolescent Health (n = 13,150). Urbanicity-stratified multivariate negative binomial regression models were used to examine cross-sectional associations between neighborhood fast food availability and individual-level self-reported fast food consumption frequency, controlling for individual and neighborhood characteristics. Results In adjusted analysis, fast food availability was not associated with weekly frequency of fast food consumption in non-urban or low- or high-density urban areas. Conclusions Policies aiming to reduce neighborhood availability as a means to reduce fast food consumption among young adults may be unsuccessful. Consideration of fast food outlets near school or workplace locations, factors specific to more or less urban settings, and the role of individual lifestyle attitudes and preferences are needed in future research. PMID:21740571

  8. SU-E-T-170: Characterization of the Location, Extent, and Proximity to Critical Structures of Target Volumes Provides Detail for Improved Outcome Predictions Among Pancreatic Cancer Patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cheng, Z; Moore, J; Rosati, L

    Purpose: In radiotherapy, size, location and proximity of the target to critical structures influence treatment decisions. It has been shown that proximity of the target predicts dosimetric sparing of critical structures. In addition to dosimetry, precise location of disease has further implications such as tumor invasion, or proximity to major arteries that inhibit surgery. Knowledge of which patients can be converted to surgical candidates by radiation may have high impact on future treat/no-treat decisions. We propose a method to improve our characterization of the location of pancreatic cancer and treatment volume extent with respect to nearby arteries with the goalmore » of developing features to improve clinical predictions and decisions. Methods: Oncospace is a local learning health system that systematically captures clinical outcomes and all aspects of radiotherapy treatment plans, including overlap volume histograms (OVH) – a measure of spatial relationships between two structures. Minimum and maximum distances of PTV and OARs based on OVH, PTV volume, anatomic location by ICD-9 code, and surgical outcome were queried. Normalized distance to center from the left and right kidney was calculated to indicate tumor location and laterality. Distance to critical arteries (celiac, superior mesenteric, common hepatic) is validated by surgical status (borderline resectable, locally advanced converted to resectable). Results: There were 205 pancreas stereotactic body radiotherapy patients treated from 2009–2015 queried. Location/laterality of tumor based on kidney OVH show strong trends between location by OVH and by ICD-9. Compared to the locally advanced group, the borderline resectable group showed larger geometrical distance from critical arteries (p=0.03). Conclusion: Our platform enabled analysis of shape/size-location relationships. These data suggest that PTV volume and attention to distance between PTVs and surrounding OARs and major arteries may be

  9. Radiotherapy treatment planning: benefits of CT-MR image registration and fusion in tumor volume delineation.

    PubMed

    Djan, Igor; Petrović, Borislava; Erak, Marko; Nikolić, Ivan; Lucić, Silvija

    2013-08-01

    Development of imaging techniques, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), made great impact on radiotherapy treatment planning by improving the localization of target volumes. Improved localization allows better local control of tumor volumes, but also minimizes geographical misses. Mutual information is obtained by registration and fusion of images achieved manually or automatically. The aim of this study was to validate the CT-MRI image fusion method and compare delineation obtained by CT versus CT-MRI image fusion. The image fusion software (XIO CMS 4.50.0) was applied to delineate 16 patients. The patients were scanned on CT and MRI in the treatment position within an immobilization device before the initial treatment. The gross tumor volume (GTV) and clinical target volume (CTV) were delineated on CT alone and on CT+MRI images consecutively and image fusion was obtained. Image fusion showed that CTV delineated on a CT image study set is mainly inadequate for treatment planning, in comparison with CTV delineated on CT-MRI fused image study set. Fusion of different modalities enables the most accurate target volume delineation. This study shows that registration and image fusion allows precise target localization in terms of GTV and CTV and local disease control.

  10. Assessment of three-dimensional setup errors in image-guided pelvic radiotherapy for uterine and cervical cancer using kilovoltage cone-beam computed tomography and its effect on planning target volume margins.

    PubMed

    Patni, Nidhi; Burela, Nagarjuna; Pasricha, Rajesh; Goyal, Jaishree; Soni, Tej Prakash; Kumar, T Senthil; Natarajan, T

    2017-01-01

    To achieve the best possible therapeutic ratio using high-precision techniques (image-guided radiation therapy/volumetric modulated arc therapy [IGRT/VMAT]) of external beam radiation therapy in cases of carcinoma cervix using kilovoltage cone-beam computed tomography (kV-CBCT). One hundred and five patients of gynecological malignancies who were treated with IGRT (IGRT/VMAT) were included in the study. CBCT was done once a week for intensity-modulated radiation therapy and daily in IGRT/VMAT. These images were registered with the planning CT scan images and translational errors were applied and recorded. In all, 2078 CBCT images were studied. The margins of planning target volume were calculated from the variations in the setup. The setup variation was 5.8, 10.3, and 5.6 mm in anteroposterior, superoinferior, and mediolateral direction. This allowed adequate dose delivery to the clinical target volume and the sparing of organ at risks. Daily kV-CBCT is a satisfactory method of accurate patient positioning in treating gynecological cancers with high-precision techniques. This resulted in avoiding geographic miss.

  11. Target detection in insects: optical, neural and behavioral optimizations.

    PubMed

    Gonzalez-Bellido, Paloma T; Fabian, Samuel T; Nordström, Karin

    2016-12-01

    Motion vision provides important cues for many tasks. Flying insects, for example, may pursue small, fast moving targets for mating or feeding purposes, even when these are detected against self-generated optic flow. Since insects are small, with size-constrained eyes and brains, they have evolved to optimize their optical, neural and behavioral target visualization solutions. Indeed, even if evolutionarily distant insects display different pursuit strategies, target neuron physiology is strikingly similar. Furthermore, the coarse spatial resolution of the insect compound eye might actually be beneficial when it comes to detection of moving targets. In conclusion, tiny insects show higher than expected performance in target visualization tasks. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Interval training in the fed or fasted state improves body composition and muscle oxidative capacity in overweight women.

    PubMed

    Gillen, Jenna B; Percival, Michael E; Ludzki, Alison; Tarnopolsky, Mark A; Gibala, Martin J

    2013-11-01

    To investigate the effects of low-volume high-intensity interval training (HIT) performed in the fasted (FAST) versus fed (FED) state on body composition, muscle oxidative capacity, and glycemic control in overweight/obese women. Sixteen women (27 ± 8 years, BMI: 29 ± 6 kg/m(2) , VO2peak : 28 ± 3 ml/kg/min) were assigned to either FAST or FED (n = 8 each) and performed 18 sessions of HIT (10× 60-s cycling efforts at ∼90% maximal heart rate, 60-s recovery) over 6 weeks. There was no significant difference between FAST and FED for any measured variable. Body mass was unchanged following training; however, dual energy X-ray absorptiometry revealed lower percent fat in abdominal and leg regions as well as the whole body level (main effects for time, P ≤ 0.05). Fat-free mass increased in leg and gynoid regions (P ≤ 0.05). Resting muscle biopsies revealed a training-induced increase in mitochondrial capacity as evidenced by increased maximal activities of citrate synthase and β-hydroxyacyl-CoA dehydrogenase (P ≤ 0.05). There was no change in insulin sensitivity, although change in insulin area under the curve was correlated with change in abdominal percent fat (r = 0.54, P ≤ 0.05). Short-term low-volume HIT is a time-efficient strategy to improve body composition and muscle oxidative capacity in overweight/obese women, but fed- versus fasted-state training does not alter this response. Copyright © 2013 The Obesity Society.

  13. Does Stroke Volume Increase During an Incremental Exercise? A Systematic Review

    PubMed Central

    Vieira, Stella S.; Lemes, Brunno; de T. C. de Carvalho, Paulo; N. de Lima, Rafael; S. Bocalini, Danilo; A. S. Junior, José; Arsa, Gisela; A. Casarin, Cezar; L. Andrade, Erinaldo; J. Serra, Andrey

    2016-01-01

    Introduction: Cardiac output increases during incremental-load exercise to meet metabolic skeletal muscle demand. This response requires a fast adjustment in heart rate and stroke volume. The heart rate is well known to increase linearly with exercise load; however, data for stroke volume during incremental-load exercise are unclear. Our objectives were to (a) review studies that have investigated stroke volume on incremental load exercise and (b) summarize the findings for stroke volume, primarily at maximal-exercise load. Methods: A comprehensive review of the Cochrane Library’s, Embase, Medline, SportDiscus, PubMed, and Web of Sci-ence databases was carried out for the years 1985 to the present. The search was performed between February and June 2014 to find studies evaluating changes in stroke volume during incremental-load exercise. Controlled and uncontrolled trials were evaluated for a quality score. Results: The stroke volume data in maximal-exercise load are inconsistent. There is evidence to hypothesis that stroke volume increases during maximal-exercise load, but other lines of evidence indicate that stroke volume reaches a plateau under these circumstances, or even decreases. Conclusion: The stroke volume are unclear, include contradictory evidence. Additional studies with standardized reporting for subjects (e.g., age, gender, physical fitness, and body position), exercise test protocols, and left ventricular function are required to clarify the characteristics of stroke volume during incremental maximal-exercise load. PMID:27347221

  14. SU-E-J-192: Verification of 4D-MRI Internal Target Volume Using Cine MRI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lafata, K; Czito, B; Palta, M

    Purpose: To investigate the accuracy of 4D-MRI in determining the Internal Target Volume (ITV) used in radiation oncology treatment planning of liver cancers. Cine MRI is used as the standard baseline in establishing the feasibility and accuracy of 4D-MRI tumor motion within the liver. Methods: IRB approval was obtained for this retrospective study. Analysis was performed on MR images from four patients receiving external beam radiation therapy for liver cancer at our institution. Eligible patients received both Cine and 4D-MRI scans before treatment. Cine images were acquired sagittally in real time at a slice bisecting the tumor, while 4D imagesmore » were acquired volumetrically. Cine MR DICOM headers were manipulated such that each respiratory frame was assigned a unique slice location. This approach permitted the treatment planning system (Eclipse, Varian Medical Systems) to recognize a complete respiratory cycle as a “volume”, where the gross tumor was contoured temporally. Software was developed to calculate the union of all frame contours in the structure set, resulting in the corresponding plane of the ITV projecting through the middle of the tumor, defined as the Internal Target Area (ITA). This was repeated for 4D-MRI, at the corresponding slice location, allowing a direct comparison of ITAs obtained from each modality. Results: Four patients have been analyzed. ITAs contoured from 4D-MRI correlate with contours from Cine MRI. The mean error of 4D values relative to Cine values is 7.67 +/− 2.55 %. No single ITA contoured from 4D-MRI demonstrated more than 10.5 % error compared to its Cine MRI counterpart. Conclusion: Motion management is a significant aspect of treatment planning within dynamic environments such as the liver, where diaphragmatic and cardiac activity influence plan accuracy. This small pilot study suggests that 4D-MRI based ITA measurements agree with Cine MRI based measurements, an important step towards clinical implementation

  15. FastChem: An ultra-fast equilibrium chemistry

    NASA Astrophysics Data System (ADS)

    Kitzmann, Daniel; Stock, Joachim

    2018-04-01

    FastChem is an equilibrium chemistry code that calculates the chemical composition of the gas phase for given temperatures and pressures. Written in C++, it is based on a semi-analytic approach, and is optimized for extremely fast and accurate calculations.

  16. Brand name logo recognition of fast food and healthy food among children.

    PubMed

    Arredondo, Elva; Castaneda, Diego; Elder, John P; Slymen, Donald; Dozier, David

    2009-02-01

    The fast food industry has been increasingly criticized for creating brand loyalty in young consumers. Food marketers are well versed in reaching children and youth given the importance of brand loyalty on future food purchasing behavior. In addition, food marketers are increasingly targeting the Hispanic population given their growing spending power. The fast food industry is among the leaders in reaching youth and ethnic minorities through their marketing efforts. The primary objective of this study was to determine if young children recognized fast food restaurant logos at a higher rate than other food brands. Methods Children (n = 155; 53% male; 87% Hispanic) ages 4-8 years were recruited from elementary schools and asked to match 10 logo cards to products depicted on a game board. Parents completed a survey assessing demographic and psychosocial characteristics associated with a healthy lifestyle in the home. Results Older children and children who were overweight were significantly more likely to recognize fast food restaurant logos than other food logos. Moreover, parents' psychosocial and socio-demographic characteristics were associated with the type of food logo recognized by the children. Conclusions Children's high recognition of fast food restaurant logos may reflect greater exposure to fast food advertisements. Families' socio-demographic characteristics play a role in children's recognition of food logos.

  17. Dissociation of biomolecules in liquid environments during fast heavy-ion irradiation

    NASA Astrophysics Data System (ADS)

    Nomura, Shinji; Tsuchida, Hidetsugu; Kajiwara, Akihiro; Yoshida, Shintaro; Majima, Takuya; Saito, Manabu

    2017-12-01

    The effect of aqueous environment on fast heavy-ion radiation damage of biomolecules was studied by comparative experiments using liquid- and gas-phase amino acid targets. Three types of amino acids with different chemical structures were used: glycine, proline, and hydroxyproline. Ion-induced reaction products were analyzed by time-of-flight secondary-ion mass spectrometry. The results showed that fragments from the amino acids resulting from the C—Cα bond cleavage were the major products for both types of targets. For liquid-phase targets, specific products originating from chemical reactions in solutions were observed. Interestingly, multiple dissociated atomic fragments were negligible for the liquid-phase targets. We found that the ratio of multifragment to total fragment ion yields was approximately half of that for gas-phase targets. This finding agreed with the results of other studies on biomolecular cluster targets. It is concluded that the suppression of molecular multifragmentation is caused by the energy dispersion to numerous water molecules surrounding the biomolecular solutes.

  18. Photoinduced local heating in silica photonic crystals for fast and reversible switching.

    PubMed

    Gallego-Gómez, Francisco; Blanco, Alvaro; López, Cefe

    2012-12-04

    Fast and reversible photonic-bandgap tunability is achieved in silica artificial opals by local heating. The effect is fully reversible as heat rapidly dissipates through the non-irradiated structure without active cooling and water is readsorbed. The performance is strongly enhanced by decreasing the photoirradiated opal volume, allowing bandgap shifts of 12 nm and response times of 20 ms. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Effects of eribulin, vincristine, paclitaxel and ixabepilone on fast axonal transport and kinesin-1 driven microtubule gliding: implications for chemotherapy-induced peripheral neuropathy.

    PubMed

    LaPointe, Nichole E; Morfini, Gerardo; Brady, Scott T; Feinstein, Stuart C; Wilson, Leslie; Jordan, Mary Ann

    2013-07-01

    Chemotherapy-induced peripheral neuropathy (CIPN) is a serious, painful and dose-limiting side effect of cancer drugs that target microtubules. The mechanisms underlying the neuronal damage are unknown, but may include disruption of fast axonal transport, an essential microtubule-based process that moves cellular components over long distances between neuronal cell bodies and nerve terminals. This idea is supported by the "dying back" pattern of degeneration observed in CIPN, and by the selective vulnerability of sensory neurons bearing the longest axonal projections. In this study, we test the hypothesis that microtubule-targeting drugs disrupt fast axonal transport using vesicle motility assays in isolated squid axoplasm and a cell-free microtubule gliding assay with defined components. We compare four clinically-used drugs, eribulin, vincristine, paclitaxel and ixabepilone. Of these, eribulin is associated with a relatively low incidence of severe neuropathy, while vincristine has a relatively high incidence. In vesicle motility assays, we found that all four drugs inhibited anterograde (conventional kinesin-dependent) fast axonal transport, with the potency being vincristine=ixabepilone>paclitaxel=eribulin. Interestingly, eribulin and paclitaxel did not inhibit retrograde (cytoplasmic dynein-dependent) fast axonal transport, in contrast to vincristine and ixabepilone. Similarly, vincristine and ixabepilone both exerted significant inhibitory effects in an in vitro microtubule gliding assay consisting of recombinant kinesin (kinesin-1) and microtubules composed of purified bovine brain tubulin, whereas paclitaxel and eribulin had negligible effects. Our results suggest that (i) inhibition of microtubule-based fast axonal transport may be a significant contributor to neurotoxicity induced by microtubule-targeting drugs, and (ii) that individual microtubule-targeting drugs affect fast axonal transport through different mechanisms. Copyright © 2013 Elsevier Inc

  20. Thinkers on Education. Volume 2.

    ERIC Educational Resources Information Center

    Morsy, Zaghloul, Ed.

    This collection of essays targets universities, social science research institutes, teacher training colleges, and those who lecture and carry out research on the history of ideas and of education. It is the second volume in a series that presents, in English, French, and Spanish, a comprehensive view of great educators of every age and culture.…

  1. Thinkers on Education. Volume 1.

    ERIC Educational Resources Information Center

    Morsy, Zaghloul, Ed.

    This collection of essays targets universities, social science research institutes, teacher training colleges, and those who lecture and carry out research on the history of ideas and of education. It is the first volume in a series that presents, in English, French, and Spanish, a comprehensive view of great educators of every age and culture.…

  2. Thinkers on Education. Volume 4.

    ERIC Educational Resources Information Center

    Morsy, Zaghloul, Ed.

    This collection of essays targets universities, social science research institutes, teacher training colleges, and those who lecture and carry out research on the history of ideas and of education. It is the fourth volume in a series that presents, in English, French, and Spanish, a comprehensive view of great educators of every age and culture.…

  3. An active target for the accelerator-based transmutation system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grebyonkin, K.F.

    1995-10-01

    Consideration is given to the possibility of radical reduction in power requirements to the proton accelerator of the electronuclear reactor due to neutron multiplication both in the blanket and the target of an active material. The target is supposed to have the fast-neutron spectrum, and the blanket-the thermal one. The blanket and the target are separated by the thermal neutrons absorber, which is responsible for the neutron decoupling of the active target and blanket. Also made are preliminary estimations which illustrate that the realization of the idea under consideration can lead to significant reduction in power requirements to the protonmore » beam and, hence considerably improve economic characteristics of the electronuclear reactor.« less

  4. Whispering Gallery Mode Resonators for Rapid Label-Free Biosensing in Small Volume Droplets

    PubMed Central

    Wildgen, Sarah M.; Dunn, Robert C.

    2015-01-01

    Rapid biosensing requires fast mass transport of the analyte to the surface of the sensing element. To optimize analysis times, both mass transport in solution and the geometry and size of the sensing element need to be considered. Small dielectric spheres, tens of microns in diameter, can act as label-free biosensors using whispering gallery mode (WGM) resonances. WGM resonances are sensitive to the effective refractive index, which changes upon analyte binding to recognition sites on functionalized resonators. The spherical geometry and tens of microns diameter of these resonators provides an efficient target for sensing while their compact size enables detection in limited volumes. Here, we explore conditions leading to rapid analyte detection using WGM resonators as label-free sensors in 10 μL sample droplets. Droplet evaporation leads to potentially useful convective mixing, but also limits the time over which analysis can be completed. We show that active droplet mixing combined with initial binding rate measurements is required for accurate nanomolar protein quantification within the first minute following injection. PMID:25806835

  5. Whispering gallery mode resonators for rapid label-free biosensing in small volume droplets.

    PubMed

    Wildgen, Sarah M; Dunn, Robert C

    2015-03-23

    Rapid biosensing requires fast mass transport of the analyte to the surface of the sensing element. To optimize analysis times, both mass transport in solution and the geometry and size of the sensing element need to be considered. Small dielectric spheres, tens of microns in diameter, can act as label-free biosensors using whispering gallery mode (WGM) resonances. WGM resonances are sensitive to the effective refractive index, which changes upon analyte binding to recognition sites on functionalized resonators. The spherical geometry and tens of microns diameter of these resonators provides an efficient target for sensing while their compact size enables detection in limited volumes. Here, we explore conditions leading to rapid analyte detection using WGM resonators as label-free sensors in 10 μL sample droplets. Droplet evaporation leads to potentially useful convective mixing, but also limits the time over which analysis can be completed. We show that active droplet mixing combined with initial binding rate measurements is required for accurate nanomolar protein quantification within the first minute following injection.

  6. Fast-Food Environments and Family Fast-Food Intake in Nonmetropolitan Areas

    PubMed Central

    Longacre, Meghan R.; Drake, Keith M.; MacKenzie, Todd A.; Gibson, Lucinda; Owens, Peter; Titus, Linda J.; Beach, Michael L.; Dalton, Madeline A.

    2012-01-01

    Background Little is known about the influence of in-town fast-food availability on family-level fast-food intake in nonmetropolitan areas. Purpose The purpose of the current study was to determine whether the presence of chain fast-food outlets was associated with fast-food intake among adolescents and parents, and to assess whether this relationship was moderated by family access to motor vehicles. Methods Telephone surveys were conducted with 1547 adolescent–parent dyads in 32 New Hampshire and Vermont communities between 2007 and 2008. Fast-food intake in the past week was measured through self-report. In-town fast-food outlets were located and enumerated using an onsite audit. Family motor vehicle access was categorized based on the number of vehicles per licensed drivers in the household. Poisson regression was used to determine unadjusted and adjusted risk ratios (RRs). Analyses were conducted in 2011. Results About half (52.1%) of adolescents and 34.7% of parents consumed fast food at least once in the past week. Adolescents and parents who lived in towns with five or more fast-food outlets were about 30% more likely to eat fast food compared to those in towns with no fast-food outlets, even after adjusting for individual, family, and town characteristics (RR=1.29, 95% CI= 1.10, 1.51; RR=1.32, 95% CI=1.07,1.62, respectively). Interaction models demonstrated that the influence of in-town fast-food outlets on fast-food intake was strongest among families with low motor vehicle access. Conclusions In nonmetropolitan areas, household transportation should be considered as an important moderator of the relationship between in-town fast-food outlets and family intake. PMID:22608373

  7. Fast-food environments and family fast-food intake in nonmetropolitan areas.

    PubMed

    Longacre, Meghan R; Drake, Keith M; MacKenzie, Todd A; Gibson, Lucinda; Owens, Peter; Titus, Linda J; Beach, Michael L; Dalton, Madeline A

    2012-06-01

    Little is known about the influence of in-town fast-food availability on family-level fast-food intake in nonmetropolitan areas. The purpose of the current study was to determine whether the presence of chain fast-food outlets was associated with fast-food intake among adolescents and parents, and to assess whether this relationship was moderated by family access to motor vehicles. Telephone surveys were conducted with 1547 adolescent-parent dyads in 32 New Hampshire and Vermont communities between 2007 and 2008. Fast-food intake in the past week was measured through self-report. In-town fast-food outlets were located and enumerated using an onsite audit. Family motor vehicle access was categorized based on the number of vehicles per licensed drivers in the household. Poisson regression was used to determine unadjusted and adjusted risk ratios (RRs). Analyses were conducted in 2011. About half (52.1%) of adolescents and 34.7% of parents consumed fast food at least once in the past week. Adolescents and parents who lived in towns with five or more fast-food outlets were about 30% more likely to eat fast food compared to those in towns with no fast-food outlets, even after adjusting for individual, family, and town characteristics (RR=1.29, 95% CI= 1.10, 1.51; RR=1.32, 95% CI=1.07, 1.62, respectively). Interaction models demonstrated that the influence of in-town fast-food outlets on fast-food intake was strongest among families with low motor vehicle access. In nonmetropolitan areas, household transportation should be considered as an important moderator of the relationship between in-town fast-food outlets and family intake. Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Deuteron Beam Driven Fast Ignition of a Pre-Compressed Inertial Confinement Fusion (ICF) Fuel Capsule

    NASA Astrophysics Data System (ADS)

    Yang, Xiaoling; Miley, George; Flippo, Kirk; Hora, Heinrich; Gaillard, Sandrine; Offermann, Dustin

    2012-10-01

    We proposed to utilize a new ``Deuterium Cluster'' type structure for the laser interaction foil to generate an energetic deuteron beam as the fast igniter to ignite inertial confinement fusion fuel capsule. The benefit of deuteron beam driven fast ignition is that its deposition in the target fuel will not only provide heating but also fuse with fuel as they slow down in the target. The preliminary results from recent laser-deuteron acceleration experiment at LANL were encouraging. Also, in most recent calculations, we found that a 12.73% extra energy gain from deuteron beam-target fusion could be achieved when quasi-Maxwellian deuteron beam was assumed, and when a ρrb = 4.5 g/cm2 was considered, where ρ is the fuel density, and rb is the ion beam focusing radius on the target. These results provide some insight into the contribution of the extra heat produced by deuteron beam-target fusion to the hot spot ignition process. If the physics works as anticipated, this novel type of interaction foil can efficiently generate energetic deuterons during intense laser pulses. The massive yield of deuterons should turn out to be the most efficient way of igniting the DT fuel, making the dream of near-term commercialization of FI fusion more achievable.

  9. Comparison of Fast-Food and Non-Fast-Food Children's Menu Items

    ERIC Educational Resources Information Center

    Serrano, Elena L.; Jedda, Virginia B.

    2009-01-01

    Objective: Compare the macronutrient content of children's meals sold by fast-food restaurants (FFR) and non-fast-food restaurants (NFF). Design: All restaurants within the designated city limits were surveyed. Non-fast-food children's meals were purchased, weighed, and analyzed using nutrition software. All fast-food children's meals were…

  10. A chest-shape target automatic detection method based on Deformable Part Models

    NASA Astrophysics Data System (ADS)

    Zhang, Mo; Jin, Weiqi; Li, Li

    2016-10-01

    Automatic weapon platform is one of the important research directions at domestic and overseas, it needs to accomplish fast searching for the object to be shot under complex background. Therefore, fast detection for given target is the foundation of further task. Considering that chest-shape target is common target of shoot practice, this paper treats chestshape target as the target and studies target automatic detection method based on Deformable Part Models. The algorithm computes Histograms of Oriented Gradient(HOG) features of the target and trains a model using Latent variable Support Vector Machine(SVM); In this model, target image is divided into several parts then we can obtain foot filter and part filters; Finally, the algorithm detects the target at the HOG features pyramid with method of sliding window. The running time of extracting HOG pyramid with lookup table can be shorten by 36%. The result indicates that this algorithm can detect the chest-shape target in natural environments indoors or outdoors. The true positive rate of detection reaches 76% with many hard samples, and the false positive rate approaches 0. Running on a PC (Intel(R)Core(TM) i5-4200H CPU) with C++ language, the detection time of images with the resolution of 640 × 480 is 2.093s. According to TI company run library about image pyramid and convolution for DM642 and other hardware, our detection algorithm is expected to be implemented on hardware platform, and it has application prospect in actual system.

  11. First Principles Analysis of Convection in the Earth's Mantle, Eustatic Sea Level and Earth Volume

    NASA Astrophysics Data System (ADS)

    Kinsland, G. L.

    2011-12-01

    Steady state convection (convection whereby heat leaving the mantle at the top is equal to the heat entering the mantle across the core mantle boundary and that created within the mantle) of the Earth's mantle is, to a very good approximation, both a constant mass and constant volume process. Mass or volume which moves to one place; e.g., an oceanic ridge; must be accompanied by mass or volume removed from another place. The location of removal, whether from underneath of an ocean or a continent, determines the relationship between oceanic ridge volume and eustatic sea level. If all of the volume entering a ridge were to come from under an oceanic basin then the size of the ridge would not affect eustatic sea level as it would be compensated by a lowering of the sea floor elsewhere. If the volume comes from under a continent then the hypsometry of the continent becomes important. Thus, eustatic sea level is not simply related to convection rate and oceanic ridge volume as posited by Hays and Pitman(1973). Non-steady state convection is still a constant mass process but is not a constant volume process. The mantle experiences a net gain of heat, warms and expands during periods of relatively slow convection (that being convection rate which is less than that necessary to transport incoming and internally created heat to the surface). Conversely, the mantle has a net loss of heat, cools and contracts during periods of relatively rapid convection. The Earth itself expands and contracts as the mantle does. During rapid convection more volume is delivered from the interior of the mantle to the Earth's ridge system than during slow convection. The integral of the difference of ridge system volume between fast and slow convection over a fast-slow convection cycle is a measure of the difference in volume of the mantle over a cycle. The magnitude of the Earth's volume expansion and contraction as calculated from published values for the volume of ocean ridges and is about

  12. Light-curve Modulation of Low-mass Stars in K2. I. Identification of 481 Fast Rotators in the Solar Neighborhood

    NASA Astrophysics Data System (ADS)

    Saylor, Dicy; Lepine, Sebastien; Crossfield, Ian; Petigura, Erik A.

    2018-01-01

    The K2 mission is targeting large numbers of nearby (d < 100 pc) GKM dwarfs selected from the SUPERBLINK proper motion survey (μ > 40 mas yr‑1, V < 20). Additionally, the mission is targeting low-mass, high proper motion stars associated with the local (d < 500 pc) Galactic halo population also selected from SUPERBLINK. K2 campaigns 0 through 8 monitored a total of 26,518 of these cool main-sequence stars. We used the auto-correlation function to search for fast rotators by identifying short-period photometric modulations in the K2 light curves. We identified 481 candidate fast rotators with rotation periods <4 days that show light-curve modulations consistent with starspots. Their kinematics show low average transverse velocities, suggesting that they are part of the young disk population. A subset (13) of the fast rotators is found among those targets with colors and kinematics consistent with the local Galactic halo population and may represent stars spun up by tidal interactions in close binary systems. We further demonstrate that the M dwarf fast rotators selected from the K2 light curves are significantly more likely to have UV excess and discuss the potential of the K2 mission to identify new nearby young GKM dwarfs on the basis of their fast rotation rates. Finally, we discuss the possible use of local halo stars as fiducial, non-variable sources in the Kepler fields.

  13. What Is the Optimal Target Convective Volume in On-Line Hemodiafiltration Therapy?

    PubMed

    Canaud, Bernard; Koehler, Katrin; Bowry, Sudhir; Stuard, Stefano

    2017-01-01

    Conventional diffusion-based dialysis modalities including high-flux hemodialysis are limited in their capacity to effectively remove large uremic toxins and to improve outcomes for end-stage chronic kidney disease (ESKD) patients. By increasing convective solute transport, hemodiafiltration (HDF) enhances solute removal capacity over a broad range of middle- and large-size uremic toxins implicated in the pathophysiology of chronic kidney disease. Furthermore, by offering flexible convection volume, on-line HDF permits customizing the treatment dose to the patient's needs. In addition, convective-based modalities have been shown to improve hemodynamic stability and to reduce patients' inflammation profile - both of which are implicated in CKD morbidity and mortality. Growing clinical evidence indicates that HDF-based modalities provide ESKD patients with a number of clinical and biological benefits, including improved outcomes. Interestingly, it has recently emerged that the clinical benefits associated with HDF are positively associated with the total ultrafiltered volume per session (and per week), namely convective dose. In this chapter, we revisit the concept of convective dose and discuss the threshold value above which an improvement in ESKD patient outcome can be expected. This particular point will be addressed by stratifying the level of efficacy of convective volumes, schematically defined as minimal, optimal, personalized, and maximal. In addition, factors and best clinical practices implicated in the achievement of an optimal convective dose are reviewed. To conclude, we show how HDF differs from standard hemodialysis and why HDF offers a paradigm shift in renal replacement therapy. © 2017 S. Karger AG, Basel.

  14. Fast and accurate Voronoi density gridding from Lagrangian hydrodynamics data

    NASA Astrophysics Data System (ADS)

    Petkova, Maya A.; Laibe, Guillaume; Bonnell, Ian A.

    2018-01-01

    Voronoi grids have been successfully used to represent density structures of gas in astronomical hydrodynamics simulations. While some codes are explicitly built around using a Voronoi grid, others, such as Smoothed Particle Hydrodynamics (SPH), use particle-based representations and can benefit from constructing a Voronoi grid for post-processing their output. So far, calculating the density of each Voronoi cell from SPH data has been done numerically, which is both slow and potentially inaccurate. This paper proposes an alternative analytic method, which is fast and accurate. We derive an expression for the integral of a cubic spline kernel over the volume of a Voronoi cell and link it to the density of the cell. Mass conservation is ensured rigorously by the procedure. The method can be applied more broadly to integrate a spherically symmetric polynomial function over the volume of a random polyhedron.

  15. Automatic target detection using binary template matching

    NASA Astrophysics Data System (ADS)

    Jun, Dong-San; Sun, Sun-Gu; Park, HyunWook

    2005-03-01

    This paper presents a new automatic target detection (ATD) algorithm to detect targets such as battle tanks and armored personal carriers in ground-to-ground scenarios. Whereas most ATD algorithms were developed for forward-looking infrared (FLIR) images, we have developed an ATD algorithm for charge-coupled device (CCD) images, which have superior quality to FLIR images in daylight. The proposed algorithm uses fast binary template matching with an adaptive binarization, which is robust to various light conditions in CCD images and saves computation time. Experimental results show that the proposed method has good detection performance.

  16. Metabolite and transcriptome analysis during fasting suggest a role for the p53-Ddit4 axis in major metabolic tissues

    PubMed Central

    2013-01-01

    Background Fasting induces specific molecular and metabolic adaptions in most organisms. In biomedical research fasting is used in metabolic studies to synchronize nutritional states of study subjects. Because there is a lack of standardization for this procedure, we need a deeper understanding of the dynamics and the molecular mechanisms in fasting. Results We investigated the dynamic changes of liver gene expression and serum parameters of mice at several time points during a 48 hour fasting experiment and then focused on the global gene expression changes in epididymal white adipose tissue (WAT) as well as on pathways common to WAT, liver, and skeletal muscle. This approach produced several intriguing insights: (i) rather than a sequential activation of biochemical pathways in fasted liver, as current knowledge dictates, our data indicates a concerted parallel response; (ii) this first characterization of the transcriptome signature of WAT of fasted mice reveals a remarkable activation of components of the transcription apparatus; (iii) most importantly, our bioinformatic analyses indicate p53 as central node in the regulation of fasting in major metabolic tissues; and (iv) forced expression of Ddit4, a fasting-regulated p53 target gene, is sufficient to augment lipolysis in cultured adipocytes. Conclusions In summary, this combination of focused and global profiling approaches provides a comprehensive molecular characterization of the processes operating during fasting in mice and suggests a role for p53, and its downstream target Ddit4, as novel components in the transcriptional response to food deprivation. PMID:24191950

  17. Duration of Fasting, Serum Lipids, and Metabolic Profile in Early Childhood.

    PubMed

    Anderson, Laura N; Maguire, Jonathon L; Lebovic, Gerald; Hanley, Anthony J; Hamilton, Jill; Adeli, Khosrow; McCrindle, Brian W; Borkhoff, Cornelia M; Parkin, Patricia C; Birken, Catherine S

    2017-01-01

    To evaluate the association between fasting duration and lipid and metabolic test results. A cross-sectional study was conducted in healthy children aged 0-6 years from The Applied Research Group for Kids! (TARGet Kids!) primary care practice network, Toronto, Canada, 2008-2013. The associations between duration of fasting at blood collection and serum lipid tests and metabolic tests were evaluated using linear regression. Among 2713 young children with blood tests the fasting time ranged from 0 to 5 hours (1st and 99th percentiles). Fasting duration was not significantly associated with total cholesterol (β = 0.006; P = .629), high-density lipoprotein (HDL) (β = 0.002; P = .708), low-density lipoprotein (β = 0.0013; P = .240), non-HDL (β = 0.004; P = .744), or triglycerides (β = -0.016; P = .084) adjusted for age, sex, body mass index, maternal ethnicity, and time of blood draw. Glucose, insulin, and homeostasis model assessment of insulin resistance were significantly associated with fasting duration, and the average percent change between 0 and 5 hours was -7.2%, -67.1%, and -69.9%, respectively. The effect of fasting on lipid or metabolic test results did not differ by age or sex; HDL and triglycerides may differ by weight status. In this cohort of healthy young children, we found little evidence to support the need for fasting prior to measurement of lipids. The effect of fasting on glucose was small and may not be clinically important. When measuring serum lipid tests in early childhood, fasting makes a very small difference. ClinicalTrials.gov: NCT0186953. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. High-Grade Glioma Radiation Therapy Target Volumes and Patterns of Failure Obtained From Magnetic Resonance Imaging and {sup 18}F-FDOPA Positron Emission Tomography Delineations From Multiple Observers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kosztyla, Robert, E-mail: rkosztyla@bccancer.bc.ca; Chan, Elisa K.; Hsu, Fred

    Purpose: The objective of this study was to compare recurrent tumor locations after radiation therapy with pretreatment delineations of high-grade gliomas from magnetic resonance imaging (MRI) and 3,4-dihydroxy-6-[{sup 18}F]fluoro-L-phenylalanine ({sup 18}F-FDOPA) positron emission tomography (PET) using contours delineated by multiple observers. Methods and Materials: Nineteen patients with newly diagnosed high-grade gliomas underwent computed tomography (CT), gadolinium contrast-enhanced MRI, and {sup 18}F-FDOPA PET/CT. The image sets (CT, MRI, and PET/CT) were registered, and 5 observers contoured gross tumor volumes (GTVs) using MRI and PET. Consensus contours were obtained by simultaneous truth and performance level estimation (STAPLE). Interobserver variability was quantified bymore » the percentage of volume overlap. Recurrent tumor locations after radiation therapy were contoured by each observer using CT or MRI. Consensus recurrence contours were obtained with STAPLE. Results: The mean interobserver volume overlap for PET GTVs (42% ± 22%) and MRI GTVs (41% ± 22%) was not significantly different (P=.67). The mean consensus volume was significantly larger for PET GTVs (58.6 ± 52.4 cm{sup 3}) than for MRI GTVs (30.8 ± 26.0 cm{sup 3}, P=.003). More than 95% of the consensus recurrence volume was within the 95% isodose surface for 11 of 12 (92%) cases with recurrent tumor imaging. Ten (91%) of these cases extended beyond the PET GTV, and 9 (82%) were contained within a 2-cm margin on the MRI GTV. One recurrence (8%) was located outside the 95% isodose surface. Conclusions: High-grade glioma contours obtained with {sup 18}F-FDOPA PET had similar interobserver agreement to volumes obtained with MRI. Although PET-based consensus target volumes were larger than MRI-based volumes, treatment planning using PET-based volumes may not have yielded better treatment outcomes, given that all but 1 recurrence extended beyond the PET GTV and most were contained by a 2

  19. Acute fasting increases somatodendritic dopamine release in the ventral tegmental area

    PubMed Central

    2015-01-01

    Fasting and food restriction alter the activity of the mesolimbic dopamine system to affect multiple reward-related behaviors. Food restriction decreases baseline dopamine levels in efferent target sites and enhances dopamine release in response to rewards such as food and drugs. In addition to releasing dopamine from axon terminals, dopamine neurons in the ventral tegmental area (VTA) also release dopamine from their soma and dendrites, and this somatodendritic dopamine release acts as an autoinhibitory signal to inhibit neighboring VTA dopamine neurons. It is unknown whether acute fasting also affects dopamine release, including the local inhibitory somatodendritic dopamine release in the VTA. In these studies, I have tested whether fasting affects the inhibitory somatodendritic dopamine release within the VTA by examining whether an acute 24-h fast affects the inhibitory postsynaptic current mediated by evoked somatodendritic dopamine release (D2R IPSC). Fasting increased the contribution of the first action potential to the overall D2R IPSC and increased the ratio of repeated D2R IPSCs evoked at short intervals. Fasting also reduced the effect of forskolin on the D2R IPSC and led to a significantly bigger decrease in the D2R IPSC in low extracellular calcium. Finally, fasting resulted in an increase in the D2R IPSCs when a more physiologically relevant train of D2R IPSCs was used. Taken together, these results indicate that fasting caused a change in the properties of somatodendritic dopamine release, possibly by increasing dopamine release, and that this increased release can be sustained under conditions where dopamine neurons are highly active. PMID:26084913

  20. Large-volume injection of sample diluents not miscible with the mobile phase as an alternative approach in sample preparation for bioanalysis: an application for fenspiride bioequivalence.

    PubMed

    Medvedovici, Andrei; Udrescu, Stefan; Albu, Florin; Tache, Florentin; David, Victor

    2011-09-01

    Liquid-liquid extraction of target compounds from biological matrices followed by the injection of a large volume from the organic layer into the chromatographic column operated under reversed-phase (RP) conditions would successfully combine the selectivity and the straightforward character of the procedure in order to enhance sensitivity, compared with the usual approach of involving solvent evaporation and residue re-dissolution. Large-volume injection of samples in diluents that are not miscible with the mobile phase was recently introduced in chromatographic practice. The risk of random errors produced during the manipulation of samples is also substantially reduced. A bioanalytical method designed for the bioequivalence of fenspiride containing pharmaceutical formulations was based on a sample preparation procedure involving extraction of the target analyte and the internal standard (trimetazidine) from alkalinized plasma samples in 1-octanol. A volume of 75 µl from the octanol layer was directly injected on a Zorbax SB C18 Rapid Resolution, 50 mm length × 4.6 mm internal diameter × 1.8 µm particle size column, with the RP separation being carried out under gradient elution conditions. Detection was made through positive ESI and MS/MS. Aspects related to method development and validation are discussed. The bioanalytical method was successfully applied to assess bioequivalence of a modified release pharmaceutical formulation containing 80 mg fenspiride hydrochloride during two different studies carried out as single-dose administration under fasting and fed conditions (four arms), and multiple doses administration, respectively. The quality attributes assigned to the bioanalytical method, as resulting from its application to the bioequivalence studies, are highlighted and fully demonstrate that sample preparation based on large-volume injection of immiscible diluents has an increased potential for application in bioanalysis.

  1. Quantitative targeting maps based on experimental investigations for a branched tube model in magnetic drug targeting

    NASA Astrophysics Data System (ADS)

    Gitter, K.; Odenbach, S.

    2011-12-01

    Magnetic drug targeting (MDT), because of its high targeting efficiency, is a promising approach for tumour treatment. Unwanted side effects are considerably reduced, since the nanoparticles are concentrated within the target region due to the influence of a magnetic field. Nevertheless, understanding the transport phenomena of nanoparticles in an artery system is still challenging. This work presents experimental results for a branched tube model. Quantitative results describe, for example, the net amount of nanoparticles that are targeted towards the chosen region due to the influence of a magnetic field. As a result of measurements, novel drug targeting maps, combining, e.g. the magnetic volume force, the position of the magnet and the net amount of targeted nanoparticles, are presented. The targeting maps are valuable for evaluation and comparison of setups and are also helpful for the design and the optimisation of a magnet system with an appropriate strength and distribution of the field gradient. The maps indicate the danger of accretion within the tube and also show the promising result of magnetic drug targeting that up to 97% of the nanoparticles were successfully targeted.

  2. Impact of 4D image quality on the accuracy of target definition.

    PubMed

    Nielsen, Tine Bjørn; Hansen, Christian Rønn; Westberg, Jonas; Hansen, Olfred; Brink, Carsten

    2016-03-01

    Delineation accuracy of target shape and position depends on the image quality. This study investigates whether the image quality on standard 4D systems has an influence comparable to the overall delineation uncertainty. A moving lung target was imaged using a dynamic thorax phantom on three different 4D computed tomography (CT) systems and a 4D cone beam CT (CBCT) system using pre-defined clinical scanning protocols. Peak-to-peak motion and target volume were registered using rigid registration and automatic delineation, respectively. A spatial distribution of the imaging uncertainty was calculated as the distance deviation between the imaged target and the true target shape. The measured motions were smaller than actual motions. There were volume differences of the imaged target between respiration phases. Imaging uncertainties of >0.4 cm were measured in the motion direction which showed that there was a large distortion of the imaged target shape. Imaging uncertainties of standard 4D systems are of similar size as typical GTV-CTV expansions (0.5-1 cm) and contribute considerably to the target definition uncertainty. Optimising and validating 4D systems is recommended in order to obtain the most optimal imaged target shape.

  3. High Intensity High Volume Interval Training Improves Endurance Performance and Induces a Nearly Complete Slow-to-Fast Fiber Transformation on the mRNA Level.

    PubMed

    Eigendorf, Julian; May, Marcus; Friedrich, Jan; Engeli, Stefan; Maassen, Norbert; Gros, Gerolf; Meissner, Joachim D

    2018-01-01

    We present here a longitudinal study determining the effects of two 3 week-periods of high intensity high volume interval training (HIHVT) (90 intervals of 6 s cycling at 250% maximum power, P max /24 s) on a cycle ergometer. HIHVT was evaluated by comparing performance tests before and after the entire training (baseline, BSL, and endpoint, END) and between the two training sets (intermediate, INT). The mRNA expression levels of myosin heavy chain (MHC) isoforms and markers of energy metabolism were analyzed in M. vastus lateralis biopsies by quantitative real-time PCR. In incremental tests peak power (P peak ) was increased, whereas V ˙ O 2peak was unaltered. Prolonged time-to-exhaustion was found in endurance tests with 65 and 80% P max at INT and END. No changes in blood levels of lipid metabolites were detected. Training-induced decreases of hematocrit indicate hypervolemia. A shift from slow MHCI/β to fast MHCIIa mRNA expression occurred after the first and second training set. The mRNA expression of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), a master regulator of oxidative energy metabolism, decreased after the second training set. In agreement, a significant decrease was also found for citrate synthase mRNA after the second training set, indicating reduced oxidative capacity. However, mRNA expression levels of glycolytic marker enzyme glyceraldehyde-3-phosphate dehydrogenase did not change after the first and second training set. HIHVT induced a nearly complete slow-to-fast fiber type transformation on the mRNA level, which, however, cannot account for the improvements of performance parameters. The latter might be explained by the well-known effects of hypervolemia on exercise performance.

  4. Fast volumetric imaging with patterned illumination via digital micro-mirror device-based temporal focusing multiphoton microscopy.

    PubMed

    Chang, Chia-Yuan; Hu, Yvonne Yuling; Lin, Chun-Yu; Lin, Cheng-Han; Chang, Hsin-Yu; Tsai, Sheng-Feng; Lin, Tzu-Wei; Chen, Shean-Jen

    2016-05-01

    Temporal focusing multiphoton microscopy (TFMPM) has the advantage of area excitation in an axial confinement of only a few microns; hence, it can offer fast three-dimensional (3D) multiphoton imaging. Herein, fast volumetric imaging via a developed digital micromirror device (DMD)-based TFMPM has been realized through the synchronization of an electron multiplying charge-coupled device (EMCCD) with a dynamic piezoelectric stage for axial scanning. The volumetric imaging rate can achieve 30 volumes per second according to the EMCCD frame rate of more than 400 frames per second, which allows for the 3D Brownian motion of one-micron fluorescent beads to be spatially observed. Furthermore, it is demonstrated that the dynamic HiLo structural multiphoton microscope can reject background noise by way of the fast volumetric imaging with high-speed DMD patterned illumination.

  5. Infrared dim target detection based on visual attention

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Lv, Guofang; Xu, Lizhong

    2012-11-01

    Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. Based on human visual attention mechanisms, an automatic detection algorithm for infrared dim target is presented. After analyzing the characteristics of infrared dim target images, the method firstly designs Difference of Gaussians (DoG) filters to compute the saliency map. Then the salient regions where the potential targets exist in are extracted by searching through the saliency map with a control mechanism of winner-take-all (WTA) competition and inhibition-of-return (IOR). At last, these regions are identified by the characteristics of the dim IR targets, so the true targets are detected, and the spurious objects are rejected. The experiments are performed for some real-life IR images, and the results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.

  6. Fast Food Jobs. National Study of Fast Food Employment.

    ERIC Educational Resources Information Center

    Charner, Ivan; Fraser, Bryna Shore

    A study examined employment in the fast-food industry. The national survey collected data from employees at 279 fast-food restaurants from seven companies. Female employees outnumbered males by two to one. The ages of those fast-food employees in the survey sample ranged from 14 to 71, with fully 70 percent being in the 16- to 20-year-old age…

  7. Technology transfer from NASA to targeted industries, volume 1

    NASA Technical Reports Server (NTRS)

    Mccain, Wayne; Schroer, Bernard J.; Souder, William E.; Spann, Mary S.; Watters, Harry; Ziemke, M. Carl

    1993-01-01

    This report summarizes the University of Alabama in Huntsville (UAH) technology transfer to three target industries with focus on the apparel manufacturing industry in Alabama. Also included in this report are an analysis of the 1992 problem statements submitted by Alabama firms, the results of the survey of 1987-88 NASA Tech Brief requests, the results of the followup to Alabama submitted problem statements, and the development of the model describing the MSFC technology transfer process.

  8. Intercepting moving targets: does memory from practice in a specific condition of target displacement affect movement timing?

    PubMed

    de Azevedo Neto, Raymundo Machado; Teixeira, Luis Augusto

    2011-05-01

    This investigation aimed at assessing the extent to which memory from practice in a specific condition of target displacement modulates temporal errors and movement timing of interceptive movements. We compared two groups practicing with certainty of future target velocity either in unchanged target velocity or in target velocity decrease. Following practice, both experimental groups were probed in the situations of unchanged target velocity and target velocity decrease either under the context of certainty or uncertainty about target velocity. Results from practice showed similar improvement of temporal accuracy between groups, revealing that target velocity decrease did not disturb temporal movement organization when fully predictable. Analysis of temporal errors in the probing trials indicated that both groups had higher timing accuracy in velocity decrease in comparison with unchanged velocity. Effect of practice was detected by increased temporal accuracy of the velocity decrease group in situations of decreased velocity; a trend consistent with the expected effect of practice was observed for temporal errors in the unchanged velocity group and in movement initiation at a descriptive level. An additional point of theoretical interest was the fast adaptation in both groups to a target velocity pattern different from that practiced. These points are discussed under the perspective of integration of vision and motor control by means of an internal forward model of external motion.

  9. Fast food: friendly?

    PubMed

    Rice, S; McAllister, E J; Dhurandhar, N V

    2007-06-01

    Fast food is routinely blamed for the obesity epidemic and consequentially excluded from professional dietary recommendations. However, several sections of society including senior citizens, low-income adult and children, minority and homeless children, or those pressed for time appear to rely on fast food as an important source of meals. Considering the dependence of these nutritionally vulnerable population groups on fast food, we examined the possibility of imaginative selection of fast food, which would attenuate the potentially unfavorable nutrient composition. We present a sample menu to demonstrate that it is possible to design a fast food menu that provides reasonable level of essential nutrients without exceeding the caloric recommendations. We would like to alert health-care professionals that fast food need not be forbidden under all circumstances, and that a fresh look at the role of fast food may enable its inclusion in meal planning for those who depend on it out of necessity, while adding flexibility.

  10. Vented target elements for use in an isotope-production reactor. [LMFBR

    DOEpatents

    Cawley, W.E.; Omberg, R.P.

    1982-08-19

    A method is described for producing tritium gas in a fast breeder reactor cooled with liquid metal. Lithium target material is placed in pins equipped with vents, and tritium gas is recovered from the coolant.

  11. Factors influencing the difference between forecasted and actual drug sales volumes under the price-volume agreement in South Korea.

    PubMed

    Park, Sun-Young; Han, Euna; Kim, Jini; Lee, Eui-Kyung

    2016-08-01

    This study analyzed factors contributing to increases in the actual sales volumes relative to forecasted volumes of drugs under price-volume agreement (PVA) policy in South Korea. Sales volumes of newly listed drugs on the national formulary are monitored under PVA policy. When actual sales volume exceeds the pre-agreed forecasted volume by 30% or more, the drug is subject to price-reduction. Logistic regression assessed the factors related to whether drugs were the PVA price-reduction drugs. A generalized linear model with gamma distribution and log-link assessed the factors influencing the increase in actual volumes compared to forecasted volume in the PVA price-reduction drugs. Of 186 PVA monitored drugs, 34.9% were price-reduction drugs. Drugs marketed by pharmaceutical companies with previous-occupation in the therapeutic markets were more likely to be PVA price-reduction drugs than drugs marketed by firms with no previous-occupation. Drugs of multinational pharmaceutical companies were more likely to be PVA price-reduction drugs than those of domestic companies. Having more alternative existing drugs was significantly associated with higher odds of being PVA price-reduction drugs. Among the PVA price-reduction drugs, the increasing rate of actual volume compared to forecasted volume was significantly higher in drugs with clinical usefulness. By focusing the negotiation efforts on those target drugs, PVA policy can be administered more efficiently with the improved predictability of the drug sales volumes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Characterization of dynamics in complex lyophilized formulations: II. Analysis of density variations in terms of glass dynamics and comparisons with global mobility, fast dynamics, and Positron Annihilation Lifetime Spectroscopy (PALS)

    PubMed Central

    Chieng, Norman; Cicerone, Marcus T.; Zhong, Qin; Liu, Ming; Pikal, Michael J.

    2013-01-01

    Amorphous HES/disaccharide (trehalose or sucrose) formulations, with and without added polyols (glycerol and sorbitol) and disaccharide formulations of human growth hormone (hGH), were prepared by freeze drying and characterized with particular interest in methodology for using high precision density measurements to evaluate free volume changes and a focus on comparisons between “free volume” changes obtained from analysis of density data, fast dynamics (local mobility), and PALS characterization of “free volume” hole size. Density measurements were performed using a helium gas pycnometer, and fast dynamics was characterized using incoherent neutron scattering spectrometer. Addition of sucrose and trehalose to hGH decreases free volume in the system with sucrose marginally more effective than trehalose, consistent with superior pharmaceutical stability of sucrose hGH formulations well below Tg relative to trehalose. We find that density data may be analyzed in terms of free volume changes by evaluation of volume changes on mixing and calculation of apparent specific volumes from the densities. Addition of sucrose to HES decreases free volume, but the effect of trehalose is not detectable above experimental error. Addition of sorbitol or glycerol to HES/trehalose base formulations appears to significantly decrease free volume, consistent with the positive impact of such additions on pharmaceutical stability (i.e., degradation) in the glassy state. Free volume changes, evaluated from density data, fast dynamics amplitude of local motion, and PALS hole size data generally are in qualitative agreement for the HES/disaccharide systems studied. All predict decreasing molecular mobility as disaccharides are added to HES. Global mobility as measured by enthalpy relaxation times, increases as disaccharides, particularly sucrose, are added to HES. PMID:23623797

  13. Simulating polar bear energetics during a seasonal fast using a mechanistic model.

    PubMed

    Mathewson, Paul D; Porter, Warren P

    2013-01-01

    In this study we tested the ability of a mechanistic model (Niche Mapper™) to accurately model adult, non-denning polar bear (Ursus maritimus) energetics while fasting during the ice-free season in the western Hudson Bay. The model uses a steady state heat balance approach, which calculates the metabolic rate that will allow an animal to maintain its core temperature in its particular microclimate conditions. Predicted weight loss for a 120 day fast typical of the 1990s was comparable to empirical studies of the population, and the model was able to reach a heat balance at the target metabolic rate for the entire fast, supporting use of the model to explore the impacts of climate change on polar bears. Niche Mapper predicted that all but the poorest condition bears would survive a 120 day fast under current climate conditions. When the fast extended to 180 days, Niche Mapper predicted mortality of up to 18% for males. Our results illustrate how environmental conditions, variation in animal properties, and thermoregulation processes may impact survival during extended fasts because polar bears were predicted to require additional energetic expenditure for thermoregulation during a 180 day fast. A uniform 3°C temperature increase reduced male mortality during a 180 day fast from 18% to 15%. Niche Mapper explicitly links an animal's energetics to environmental conditions and thus can be a valuable tool to help inform predictions of climate-related population changes. Since Niche Mapper is a generic model, it can make energetic predictions for other species threatened by climate change.

  14. Simulating Polar Bear Energetics during a Seasonal Fast Using a Mechanistic Model

    PubMed Central

    Mathewson, Paul D.; Porter, Warren P.

    2013-01-01

    In this study we tested the ability of a mechanistic model (Niche Mapper™) to accurately model adult, non-denning polar bear (Ursus maritimus) energetics while fasting during the ice-free season in the western Hudson Bay. The model uses a steady state heat balance approach, which calculates the metabolic rate that will allow an animal to maintain its core temperature in its particular microclimate conditions. Predicted weight loss for a 120 day fast typical of the 1990s was comparable to empirical studies of the population, and the model was able to reach a heat balance at the target metabolic rate for the entire fast, supporting use of the model to explore the impacts of climate change on polar bears. Niche Mapper predicted that all but the poorest condition bears would survive a 120 day fast under current climate conditions. When the fast extended to 180 days, Niche Mapper predicted mortality of up to 18% for males. Our results illustrate how environmental conditions, variation in animal properties, and thermoregulation processes may impact survival during extended fasts because polar bears were predicted to require additional energetic expenditure for thermoregulation during a 180 day fast. A uniform 3°C temperature increase reduced male mortality during a 180 day fast from 18% to 15%. Niche Mapper explicitly links an animal’s energetics to environmental conditions and thus can be a valuable tool to help inform predictions of climate-related population changes. Since Niche Mapper is a generic model, it can make energetic predictions for other species threatened by climate change. PMID:24019883

  15. Fast Ss-Ilm a Computationally Efficient Algorithm to Discover Socially Important Locations

    NASA Astrophysics Data System (ADS)

    Dokuz, A. S.; Celik, M.

    2017-11-01

    Socially important locations are places which are frequently visited by social media users in their social media lifetime. Discovering socially important locations provide several valuable information about user behaviours on social media networking sites. However, discovering socially important locations are challenging due to data volume and dimensions, spatial and temporal calculations, location sparseness in social media datasets, and inefficiency of current algorithms. In the literature, several studies are conducted to discover important locations, however, the proposed approaches do not work in computationally efficient manner. In this study, we propose Fast SS-ILM algorithm by modifying the algorithm of SS-ILM to mine socially important locations efficiently. Experimental results show that proposed Fast SS-ILM algorithm decreases execution time of socially important locations discovery process up to 20 %.

  16. Optimization of large-volume injection for the determination of polychlorinated biphenyls in children's fast-food menus by low-resolution mass spectrometry.

    PubMed

    Esteve-Turrillas, Francesc A; Caupos, Emilie; Llorca, Isabel; Pastor, Agustín; de la Guardia, Miguel

    2008-03-26

    This study includes the determination of five indicator polychlorinated biphenyls (PCBs) (52, 101, 153, 138, and 180), six non-ortho PCBs (35, 80, 81, 77, 126, and 169), and two mono-ortho PCBs (28 and 118) in fast food for children. A freeze-dried sample of 10 g is extracted by using pressurized n-hexane in two 5 min cycles at 120 degrees C and 100 mbar. Fatty extracts were cleaned up by means of acetonitrile/n-hexane partitioning and gel-permeation chromatography. The fractionation of non-ortho, mono-ortho, and indicator PCBs was made on graphitized carbon solid-phase extraction cartridges by using n-hexane, n-hexane/toluene (99:1, v/v), and toluene as elution solvents. Gas chromatography coupled to tandem mass spectrometry and large-volume injections with a programmed-temperature vaporizer (PTV-LV) were used to increase sensitivity and selectivity of the PCB determination. The PTV-LV injection settings, that is, vaporizing temperature, vaporizing time, and purge flow, were optimized by using a central composite design. A 15-40 times increased sensitivity was reached as compared with that obtained with the conventional 1 microL splitless injection. The limits of detection achieved were between 0.3 and 1.2 pg/g, and repeatability data, as relative standard deviation varied, ranged from 2 to 9% for the 0.05 ng/mL PCB level.

  17. Alternate Tritium Production Methods Using A Liquid Lithium Target

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilson, J.

    For over 60 years, the Savannah River Site’s primary mission has been the production of tritium. From the beginning, the Savannah River National Laboratory (SRNL) has provided the technical foundation to ensure the successful execution of this critical defense mission. SRNL has developed most of the processes used in the tritium mission and provides the research and development necessary to supply this critical component. This project was executed by first developing reactor models that could be used as a neutron source. In parallel to this development calculations were carried out testing the feasibility of accelerator technologies that could also bemore » used for tritium production. Targets were designed with internal moderating material and optimized target was calculated to be capable of 3000 grams using a 1400 MWt sodium fast reactor, 850 grams using a 400 MWt sodium fast reactor, and 100 grams using a 62 MWt reactor, annually.« less

  18. Validation of the RIDASCREEN(®)FAST Milk Kit.

    PubMed

    Weiss, Thomas; Lacorn, Markus; Flannery, Jonathan; Benzinger, M Joseph; Bird, Patrick; Crowley, Erin S; Goins, Dave; Agin, James R; Gilani, Sarwar; Poepping, Bert; Garber, Eric

    2016-01-01

    The RIDASCREEN(®)FAST Milk test is a sandwich ELISA for the rapid quantification of milk proteins in various foods. The specific antibodies target casein and β-lactoglobulin. Samples are extracted and can then be analyzed in less than 40 min. The calibration curve covers a range from 2.5 to 67.5 mg/kg milk protein. The assay was validated with cookies, infant formula, chocolate dessert, ice cream, and sausages. All negative samples were found well below the LOQ of 2.5 mg/kg. Recoveries of the spiked samples were mostly in the range of 80-120%. The LOD of the ELISA was found below 1 mg/kg. The analysis of 39 different substances of interest revealed that no cross-reactivity above the LOQ occurred. Ruggedness testing proved that variations in incubation temperature, reagent volume, incubation time, extraction temperature, and extraction time had no significant influence. The stability at 4-8°C of three independent lots was investigated and found to exceed 18 months. Very good lot-to-lot consistency and no significant loss of the analytical capacity over the shelf life were observed. Incurred cookies and chocolate dessert samples were prepared and analyzed by an independent laboratory; mean recoveries of 94.4 and 102.2% and mean SDs of 10.9 and 6.3%, respectively, were found. For the 0 mg/kg level for both materials, all samples tested returned values of <2.5 mg/kg. Therefore, the analytical performance claims of the manufacturer were confirmed.

  19. Nodal weighting factor method for ex-core fast neutron fluence evaluation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chiang, R. T.

    The nodal weighting factor method is developed for evaluating ex-core fast neutron flux in a nuclear reactor by utilizing adjoint neutron flux, a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV, the unit fission source, and relative assembly nodal powers. The method determines each nodal weighting factor for ex-core neutron fast flux evaluation by solving the steady-state adjoint neutron transport equation with a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV as the adjoint source, by integrating the unit fission source with a typical fission spectrum to the solved adjointmore » flux over all energies, all angles and given nodal volume, and by dividing it with the sum of all nodal weighting factors, which is a normalization factor. Then, the fast neutron flux can be obtained by summing the various relative nodal powers times the corresponding nodal weighting factors of the adjacent significantly contributed peripheral assembly nodes and times a proper fast neutron attenuation coefficient over an operating period. A generic set of nodal weighting factors can be used to evaluate neutron fluence at the same location for similar core design and fuel cycles, but the set of nodal weighting factors needs to be re-calibrated for a transition-fuel-cycle. This newly developed nodal weighting factor method should be a useful and simplified tool for evaluating fast neutron fluence at selected locations of interest in ex-core components of contemporary nuclear power reactors. (authors)« less

  20. Proposed definition of the vaginal cuff and paracolpium clinical target volume in postoperative uterine cervical cancer.

    PubMed

    Murakami, Naoya; Norihisa, Yoshiki; Isohashi, Fumiaki; Murofushi, Keiko; Ariga, Takuro; Kato, Tomoyasu; Inaba, Koji; Okamoto, Hiroyuki; Ito, Yoshinori; Toita, Takafumi; Itami, Jun

    2016-01-01

    The aim of this study was to develop an appropriate definition for vaginal cuff and paracolpium clinical target volume (CTV) for postoperative intensity modulated radiation therapy in patients with uterine cervical cancer. A working subgroup was organized within the Radiation Therapy Study Group of the Japan Clinical Oncology Group to develop a definition for the postoperative vaginal cuff and paracolpium CTV in December 2013. The group consisted of 5 radiation oncologists who specialized in gynecologic oncology and a gynecologic oncologist. A comprehensive literature review that included anatomy, surgery, and imaging fields was performed and was followed by multiple discreet face-to-face discussions and e-mail messages before a final consensus was reached. Definitions for the landmark structures in all directions that demarcate the vaginal cuff and paracolpium CTV were decided by consensus agreement of the working group. A table was created that showed boundary structures of the vaginal cuff and paracolpium CTV in each direction. A definition of the postoperative cervical cancer vaginal cuff and paracolpium CTV was developed. It is expected that this definition guideline will serve as a template for future radiation therapy clinical trial protocols, especially protocols involving intensity modulated radiation therapy. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  1. Associations among circulating branched-chain amino acids and tyrosine with muscle volume and glucose metabolism in individuals without diabetes.

    PubMed

    Honda, Tatsuro; Kobayashi, Yoshinao; Togashi, Kenji; Hasegawa, Hiroshi; Iwasa, Motoh; Taguchi, Osamu; Takei, Yoshiyuki; Sumida, Yasuhiro

    2016-05-01

    Amino acid metabolites, including branched-chain amino acids (BCAA) and tyrosine (Tyr), affect glucose metabolism. The effects of BCAA on insulin resistance in patients with diabetes seem to conflict with mechanisms determined in animal models and cultured cells. The aim of this study was to clarify the controversy surrounding the effects of BCAA by investigating the physiological effects of BCAA and Tyr on glucose metabolism in healthy community dwellers. We investigated associations among BCAA and Tyr and metabolic parameters in 78 residents (median age, 52 y) of Mie, Japan, who did not have prediabetes, diabetes, or a body mass index >30 kg/m(2). Muscle volume, serum BCAA, and Tyr levels were higher in men than in women (n = 32 and 46, respectively; all P < 0.0001). Stepwise multiple regression analysis associated BCAA positively with muscle volume (regression coefficient/t/p/95% confidence interval, 281.8/3.7/0.0004/129.7-433.8), fasting blood glucose (FBG; 12699.4/3.22/0.0020/4830.9-20567.8), fasting immunoreactive insulin (IRI; 8505.1/2.75/0.0078/2322.5-14687.6), and homeostasis model assessment of β-cell function (HOMA-β; 893.6/2.58/0.0122/201.8-1585.5), and negatively with the HOMA-insulin resistance (HOMA-IR; -9294.1/-2.89/0.0052/-15711.0 to -2877.1). Tyr positively correlated with fasting IRI (26/2.77/0.0072/7.3-44.7). Insulin sensitivity and muscle volume are positively associated with BCAA in individuals without diabetes. In turn, BCAA correlate with increased FBG and fasting IRI levels. Tyr correlated with fasting IRI, but not with insulin sensitivity. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. 3D liver volume reconstructed for palpation training.

    PubMed

    Tibamoso, Gerardo; Perez-Gutierrez, Byron; Uribe-Quevedo, Alvaro

    2013-01-01

    Virtual Reality systems for medical procedures such as the palpation of different organs, requires fast, robust, accurate and reliable computational methods for providing realism during interaction with the 3D biological models. This paper presents the segmentation, reconstruction and palpation simulation of a healthy liver volume as a tool for training. The chosen method considers the mechanical characteristics and liver properties for correctly simulating palpation interactions, which results appropriate as a complementary tool for training medical students in familiarizing with the liver anatomy.

  3. Kidney volume measurement methods for clinical studies on autosomal dominant polycystic kidney disease

    PubMed Central

    Sharma, Kanishka; Caroli, Anna; Quach, Le Van; Petzold, Katja; Bozzetto, Michela; Serra, Andreas L.; Remuzzi, Giuseppe; Remuzzi, Andrea

    2017-01-01

    Background In autosomal dominant polycystic kidney disease (ADPKD), total kidney volume (TKV) is regarded as an important biomarker of disease progression and different methods are available to assess kidney volume. The purpose of this study was to identify the most efficient kidney volume computation method to be used in clinical studies evaluating the effectiveness of treatments on ADPKD progression. Methods and findings We measured single kidney volume (SKV) on two series of MR and CT images from clinical studies on ADPKD (experimental dataset) by two independent operators (expert and beginner), twice, using all of the available methods: polyline manual tracing (reference method), free-hand manual tracing, semi-automatic tracing, Stereology, Mid-slice and Ellipsoid method. Additionally, the expert operator also measured the kidney length. We compared different methods for reproducibility, accuracy, precision, and time required. In addition, we performed a validation study to evaluate the sensitivity of these methods to detect the between-treatment group difference in TKV change over one year, using MR images from a previous clinical study. Reproducibility was higher on CT than MR for all methods, being highest for manual and semiautomatic contouring methods (planimetry). On MR, planimetry showed highest accuracy and precision, while on CT accuracy and precision of both planimetry and Stereology methods were comparable. Mid-slice and Ellipsoid method, as well as kidney length were fast but provided only a rough estimate of kidney volume. The results of the validation study indicated that planimetry and Stereology allow using an importantly lower number of patients to detect changes in kidney volume induced by drug treatment as compared to other methods. Conclusions Planimetry should be preferred over fast and simplified methods for accurately monitoring ADPKD progression and assessing drug treatment effects. Expert operators, especially on MR images, are required

  4. "Fast" Capitalism and "Fast" Schools: New Realities and New Truths.

    ERIC Educational Resources Information Center

    Robertson, Susan L.

    This paper locates the phenomenon of self-managing schools within the framework of "fast capitalism" and identifies themes of organization central to fast capitalism, which are argued to also underpin the self-managing schools. "Fast capitalism" refers to the rapidly intensified integration of regionalized productive activities into the global…

  5. Target Fabrication Technology and New Functional Materials for Laser Fusion and Laser-Plasma Experiment

    NASA Astrophysics Data System (ADS)

    Nagai, Keiji; Norimatsu, Takayoshi; Izawa, Yasukazu

    Target fabrication technique is a key issue of laser fusion. We present a comprehensive, up-to-data compilation of laser fusion target fabrication and relating new materials. To achieve highly efficient laser implosion, organic and inorganic highly spherical millimeter-sized capsules and cryogenic hydrogen layers inside should be uniform in diameter and thickness within sub-micrometer ˜ nanometer error. Porous structured targets and molecular cluster targets are required for laser-plasma experiments and applications. Various technologies and new materials concerning above purposes are summarized including fast-ignition targets, equation-of-state measurement targets, high energy ion generation targets, etc.

  6. Characterization of Large Volume CLYC Scintillators for Nuclear Security Applications

    NASA Astrophysics Data System (ADS)

    Soundara-Pandian, Lakshmi; Tower, J.; Hines, C.; O'Dougherty, P.; Glodo, J.; Shah, K.

    2017-07-01

    We report on our development of large volume Cs2LiYCl6 (CLYC) detectors for nuclear security applications. Three-inch diameter boules have been grown and 3-in right cylinders have been fabricated. Crystals containing either >95% 6Li or >99% 7Li have been grown for applications specific to thermal or fast neutron detection, respectively. We evaluated their gamma and neutron detection properties and the performance is as good as small size crystals. Gamma and neutron efficiencies were measured for large crystals and compared with smaller size crystals. With their excellent performance characteristics, and the ability to detect fast neutrons, CLYC detectors are excellent triple-mode scintillators for use in handheld and backpack instruments for nuclear security applications.

  7. Engineering nucleases for gene targeting: safety and regulatory considerations.

    PubMed

    Pauwels, Katia; Podevin, Nancy; Breyer, Didier; Carroll, Dana; Herman, Philippe

    2014-01-25

    Nuclease-based gene targeting (NBGT) represents a significant breakthrough in targeted genome editing since it is applicable from single-celled protozoa to human, including several species of economic importance. Along with the fast progress in NBGT and the increasing availability of customized nucleases, more data are available about off-target effects associated with the use of this approach. We discuss how NBGT may offer a new perspective for genetic modification, we address some aspects crucial for a safety improvement of the corresponding techniques and we also briefly relate the use of NBGT applications and products to the regulatory oversight. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Converter target chemistry - A new challenge to radioanalytical chemistry.

    PubMed

    Choudhury, Dibyasree; Lahiri, Susanta

    2018-07-01

    The 1-2 GeV proton induced spallation reaction on the high Z materials like Hg, or lead bismuth eutectic (LBE), popularly known as converter targets, will produce strong flux of fast neutrons which would further react with fissile materials to produce intense radioactive ion beam (RIB). LBE offers suitability for use as converters over Hg but it suffers from the demerit of radiotoxic polonium production. These targets may be viewed as a store house of clinically important and other exotic radionuclides. For application of those radionuclides, radiochemical separation from bulk target material is of utmost importance. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Limitations of the planning organ at risk volume (PRV) concept.

    PubMed

    Stroom, Joep C; Heijmen, Ben J M

    2006-09-01

    Previously, we determined a planning target volume (PTV) margin recipe for geometrical errors in radiotherapy equal to M(T) = 2 Sigma + 0.7 sigma, with Sigma and sigma standard deviations describing systematic and random errors, respectively. In this paper, we investigated margins for organs at risk (OAR), yielding the so-called planning organ at risk volume (PRV). For critical organs with a maximum dose (D(max)) constraint, we calculated margins such that D(max) in the PRV is equal to the motion averaged D(max) in the (moving) clinical target volume (CTV). We studied margins for the spinal cord in 10 head-and-neck cases and 10 lung cases, each with two different clinical plans. For critical organs with a dose-volume constraint, we also investigated whether a margin recipe was feasible. For the 20 spinal cords considered, the average margin recipe found was: M(R) = 1.6 Sigma + 0.2 sigma with variations for systematic and random errors of 1.2 Sigma to 1.8 Sigma and -0.2 sigma to 0.6 sigma, respectively. The variations were due to differences in shape and position of the dose distributions with respect to the cords. The recipe also depended significantly on the volume definition of D(max). For critical organs with a dose-volume constraint, the PRV concept appears even less useful because a margin around, e.g., the rectum changes the volume in such a manner that dose-volume constraints stop making sense. The concept of PRV for planning of radiotherapy is of limited use. Therefore, alternative ways should be developed to include geometric uncertainties of OARs in radiotherapy planning.

  10. Fast word reading in pure alexia: "fast, yet serial".

    PubMed

    Bormann, Tobias; Wolfer, Sascha; Hachmann, Wibke; Neubauer, Claudia; Konieczny, Lars

    2015-01-01

    Pure alexia is a severe impairment of word reading in which individuals process letters serially with a pronounced length effect. Yet, there is considerable variation in the performance of alexic readers with generally very slow, but also occasionally fast responses, an observation addressed rarely in previous reports. It has been suggested that "fast" responses in pure alexia reflect residual parallel letter processing or that they may even be subserved by an independent reading system. Four experiments assessed fast and slow reading in a participant (DN) with pure alexia. Two behavioral experiments investigated frequency, neighborhood, and length effects in forced fast reading. Two further experiments measured eye movements when DN was forced to read quickly, or could respond faster because words were easier to process. Taken together, there was little support for the proposal that "qualitatively different" mechanisms or reading strategies underlie both types of responses in DN. Instead, fast responses are argued to be generated by the same serial-reading strategy.

  11. A Compatible Stem Taper-Volume-Weight System For Intensively Managed Fast Growing Loblolly Pine

    Treesearch

    Yugia Zhang; Bruce E. Borders; Robert L Bailey

    2002-01-01

    eometry-oriented methodology yielded a compatible taper-volume-weight system of models whose parameters were estimated using data from intensively managed loblolly pine (Pinus taeda L.) plantations in the lower coastal plain of Georgia. Data analysis showed that fertilization has significantly reduced taper (inside and outside bark) on the upper...

  12. Hunger and thirst numeric rating scales are not valid estimates for gastric content volumes: a prospective investigation in healthy children.

    PubMed

    Buehrer, Sabin; Hanke, Ursula; Klaghofer, Richard; Fruehauf, Melanie; Weiss, Markus; Schmitz, Achim

    2014-03-01

    A rating scale for thirst and hunger was evaluated as a noninvasive, simple and commonly available tool to estimate preanesthetic gastric volume, a surrogate parameter for the risk of perioperative pulmonary aspiration, in healthy volunteer school age children. Numeric scales with scores from 0 to 10 combined with smileys to rate thirst and hunger were analyzed and compared with residual gastric volumes as measured by magnetic resonance imaging and fasting times in three settings: before and for 2 h after drinking clear fluid (group A, 7 ml/kg), before and for 4 vs 6 h after a light breakfast followed by clear fluid (7 ml/kg) after 2 vs 4 h (crossover, group B), and before and for 1 h after drinking clear fluid (crossover, group C, 7 vs 3 ml/kg). In 30 children aged 6.4-12.8 (median 9.8) years, participating on 1-5 (median two) study days, 496 sets of scores and gastric volumes were determined. Large inter- and intra-individual variations were seen at baseline and in response to fluid and food intake. Significant correlations were found between hunger and thirst ratings in all groups, with children generally being more hungry than thirsty. Correlations between scores and duration of fasting or gastric residual volumes were poor to moderate. Receiver operating characteristic (ROC) analysis revealed that thirst and hunger rating scales cannot predict gastric content. Hunger and thirst scores vary considerably inter- and intra-individually and cannot predict gastric volume, nor do they correlate with fasting times in school age children. © 2013 John Wiley & Sons Ltd.

  13. Transport and spatial energy deposition of relativistic electrons in copper-doped fast ignition plasmas

    DOE PAGES

    Jarrott, L. C.; McGuffey, C.; Beg, F. N.; ...

    2017-10-24

    Fast electron transport and spatial energy deposition are investigated in integrated cone-guided Fast Ignition experiments by measuring fast electron induced copper K-shell emission using a copper tracer added to deuterated plastic shells with a geometrically reentrant gold cone. Experiments were carried out at the Laboratory for Laser Energetics on the OMEGA/OMEGA-EP Laser where the plastic shells were imploded using 54 of the 60 OMEGA60 beams (3ω, 20 kJ), while the high intensity OMEGA-EP (BL2) beam (1 ω, 10 ps, 500 J, I peak > 10 19 W/cm 2) was focused onto the inner cone tip. Here, a retrograde analysis usingmore » the hybrid-PIC electron transport code, ZUMA, is performed to examine the sensitivity of the copper Kα spatial profile on the laser-produced fast electrons, facilitating the optimization of new target point designs and laser configurations to improve the compressed core areal density by a factor of 4 and the fast electron energy coupling by a factor of 3.5.« less

  14. Youth Attitude Tracking Study. Volume 1. Spring 1980.

    DTIC Science & Technology

    1980-08-01

    JobICharacteristics 11 Active Duty Positive Propensity Respondents Target Market Profile 13 Advertising Awareness 14 ’LIAttitudes Toward Enlistment Incentives...service advertising awareness. The fact that target market men value job characteristics that pertain to improving oneself suggests that this change in copy...W,0-R143 ii4 YOUTH ATTITUDE TRACKING STUDY VOLUME i SPRING i988(U) 1/3 MARKET FACTS INC CHICAGO IL PUBLIC SECTOR RESEARCH CORP J T HEISLER AUG 80

  15. Research on Aircraft Target Detection Algorithm Based on Improved Radial Gradient Transformation

    NASA Astrophysics Data System (ADS)

    Zhao, Z. M.; Gao, X. M.; Jiang, D. N.; Zhang, Y. Q.

    2018-04-01

    Aiming at the problem that the target may have different orientation in the unmanned aerial vehicle (UAV) image, the target detection algorithm based on the rotation invariant feature is studied, and this paper proposes a method of RIFF (Rotation-Invariant Fast Features) based on look up table and polar coordinate acceleration to be used for aircraft target detection. The experiment shows that the detection performance of this method is basically equal to the RIFF, and the operation efficiency is greatly improved.

  16. Gradient rotating outer volume excitation (GROOVE): A novel method for single-shot two-dimensional outer volume suppression.

    PubMed

    Powell, Nathaniel J; Jang, Albert; Park, Jang-Yeon; Valette, Julien; Garwood, Michael; Marjańska, Małgorzata

    2015-01-01

    To introduce a new outer volume suppression (OVS) technique that uses a single pulse and rotating gradients to accomplish frequency-swept excitation. This new technique, which is called gradient rotating outer volume excitation (GROOVE), produces a circular or elliptical suppression band rather than suppressing the entire outer volume. Theoretical and k-space descriptions of GROOVE are provided. The properties of GROOVE were investigated with simulations, phantom, and human experiments performed using a 4T horizontal bore magnet equipped with a TEM coil. Similar suppression performance was obtained in phantom and human brain using GROOVE with circular and elliptical shapes. Simulations indicate that GROOVE requires less SAR and time than traditional OVS schemes, but traditional schemes provide a sharper transition zone and less residual signal. GROOVE represents a new way of performing OVS in which spins are excited temporally in space on a trajectory that can be tailored to fit the shape of the suppression region. In addition, GROOVE is capable of suppressing tailored regions of space with more flexibility and in a shorter period of time than conventional methods. GROOVE provides a fast, low SAR alternative to conventional OVS methods in some applications (e.g., scalp suppression). © 2014 Wiley Periodicals, Inc.

  17. Targeted Prostate Thermal Therapy with Catheter-Based Ultrasound Devices and MR Thermal Monitoring

    NASA Astrophysics Data System (ADS)

    Diederich, Chris; Ross, Anthony; Kinsey, Adam; Nau, Will H.; Rieke, Viola; Butts Pauly, Kim; Sommer, Graham

    2006-05-01

    Catheter-based ultrasound devices have significant advantages for thermal therapy procedures, including potential for precise spatial and dynamic control of heating patterns to conform to targeted volumes. Interstitial and transurethral ultrasound applicators, with associated treatment strategies, were developed for thermal ablation of prostate combined with MR thermal monitoring. Four types of multielement transurethral applicators were devised, each with different levels of selectivity and intended therapeutic goals: sectored tubular transducer devices with fixed directional heating patterns; planar and lightly focused curvilinear devices with narrow heating patterns; and multi-sectored tubular devices capable of dynamic angular control without applicator movement. These devices are integrated with a 4 mm delivery catheter, incorporate an inflatable cooling balloon (10 mm OD) for positioning within the prostate and capable of rotation via an MR-compatible motor. Similarly, interstitial devices (2.4 mm OD) have been developed for percutaneous implantation with fixed directional heating patterns (e.g., 180 deg.). In vivo experiments in canine prostate (n=15) under MR temperature imaging were used to evaluate the heating technology and develop treatment strategies. MR thermal imaging in a 0.5 T interventional MRI was used to monitor temperature contours and thermal dose in multiple slices through the target volume. Sectored transurethral devices produce directional coagulation zones, extending 15-20 mm radial distance to the outer prostate capsule. The curvilinear applicator produces distinct 2-3 mm wide lesions, and with sequential rotation and modulated dwell time can precisely conform thermal ablation to selected areas or the entire prostate gland. Multi-sectored transurethral applicators can dynamically control the angular heating profile and target large regions of the gland in short treatment times without applicator manipulation. Interstitial implants with

  18. Formulation design of taste-masked particles, including famotidine, for an oral fast-disintegrating dosage form.

    PubMed

    Mizumoto, Takao; Tamura, Tetsuya; Kawai, Hitoshi; Kajiyama, Atsushi; Itai, Shigeru

    2008-04-01

    In this study, the taste-masking of famotidine, which could apply to any fast-disintegrating tablet, was investigated using the spray-dry method. The target characteristics of taste-masked particles were set as follows: the dissolution rate is not to be more than 30% at 1 min and not less than 85% at 15 min, and the particle size is not to be more than 150 microm in diameter to avoid a gritty feeling in the mouth. The target dissolution profiles of spray-dried particles consisting of Aquacoat ECD30 and Eudragit NE30D or triacetin was accomplished by the screening of formulas and the appropriate lab-scale manufacturing conditions. Lab-scale testing produced taste-masked particles that met the formulation targets. On the pilot scale, spray-dried particles with attributes, such as dissolution rate and particle size, of the same quality were produced, and reproducibility was also confirmed. This confirmed that the spray-dry method produced the most appropriate taste-masked particles for fast-disintegrating dosage forms.

  19. High Resolution Melting Analysis Targeting hsp70 as a Fast and Efficient Method for the Discrimination of Leishmania Species.

    PubMed

    Zampieri, Ricardo Andrade; Laranjeira-Silva, Maria Fernanda; Muxel, Sandra Marcia; Stocco de Lima, Ana Carolina; Shaw, Jeffrey Jon; Floeter-Winter, Lucile Maria

    2016-02-01

    Protozoan parasites of the genus Leishmania cause a large spectrum of clinical manifestations known as Leishmaniases. These diseases are increasingly important public health problems in many countries both within and outside endemic regions. Thus, an accurate differential diagnosis is extremely relevant for understanding epidemiological profiles and for the administration of the best therapeutic protocol. Exploring the High Resolution Melting (HRM) dissociation profiles of two amplicons using real time polymerase chain reaction (real-time PCR) targeting heat-shock protein 70 coding gene (hsp70) revealed differences that allowed the discrimination of genomic DNA samples of eight Leishmania species found in the Americas, including Leishmania (Leishmania) infantum chagasi, L. (L.) amazonensis, L. (L.) mexicana, L. (Viannia) lainsoni, L. (V.) braziliensis, L. (V.) guyanensis, L. (V.) naiffi and L. (V.) shawi, and three species found in Eurasia and Africa, including L. (L.) tropica, L. (L.) donovani and L. (L.) major. In addition, we tested DNA samples obtained from standard promastigote culture, naturally infected phlebotomines, experimentally infected mice and clinical human samples to validate the proposed protocol. HRM analysis of hsp70 amplicons is a fast and robust strategy that allowed for the detection and discrimination of all Leishmania species responsible for the Leishmaniases in Brazil and Eurasia/Africa with high sensitivity and accuracy. This method could detect less than one parasite per reaction, even in the presence of host DNA.

  20. Proximity to Fast-Food Outlets and Supermarkets as Predictors of Fast-Food Dining Frequency.

    PubMed

    Athens, Jessica K; Duncan, Dustin T; Elbel, Brian

    2016-08-01

    This study used cross-sectional data to test the independent relationship of proximity to chain fast-food outlets and proximity to full-service supermarkets on the frequency of mealtime dining at fast-food outlets in two major urban areas, using three approaches to define access. Interactions between presence of a supermarket and presence of fast-food outlets as predictors of fast-food dining were also tested. Residential intersections for respondents in point-of-purchase and random-digit-dial telephone surveys of adults in Philadelphia, PA, and Baltimore, MD, were geocoded. The count of fast-food outlets and supermarkets within quarter-mile, half-mile, and 1-mile street network buffers around each respondent's intersection was calculated, as well as distance to the nearest fast-food outlet and supermarket. These variables were regressed on weekly fast-food dining frequency to determine whether proximity to fast food and supermarkets had independent and joint effects on fast-food dining. The effect of access to supermarkets and chain fast-food outlets varied by study population. Among telephone survey respondents, supermarket access was the only significant predictor of fast-food dining frequency. Point-of-purchase respondents were generally unaffected by proximity to either supermarkets or fast-food outlets. However, ≥1 fast-food outlet within a 1-mile buffer was an independent predictor of consuming more fast-food meals among point-of-purchase respondents. At the quarter-mile distance, ≥1 supermarket was predictive of fewer fast-food meals. Supermarket access was associated with less fast-food dining among telephone respondents, whereas access to fast-food outlets were associated with more fast-food visits among survey respondents identified at point-of-purchase. This study adds to the existing literature on geographic determinants of fast-food dining behavior among urban adults in the general population and those who regularly consume fast food. Copyright

  1. FastID: Extremely Fast Forensic DNA Comparisons

    DTIC Science & Technology

    2017-05-19

    FastID: Extremely Fast Forensic DNA Comparisons Darrell O. Ricke, PhD Bioengineering Systems & Technologies Massachusetts Institute of...Technology Lincoln Laboratory Lexington, MA USA Darrell.Ricke@ll.mit.edu Abstract—Rapid analysis of DNA forensic samples can have a critical impact on...time sensitive investigations. Analysis of forensic DNA samples by massively parallel sequencing is creating the next gold standard for DNA

  2. Atlas-Based Segmentation Improves Consistency and Decreases Time Required for Contouring Postoperative Endometrial Cancer Nodal Volumes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, Amy V.; Department of Radiation Oncology, St. Luke's-Roosevelt Hospital, New York, NY; Wortham, Angela

    2011-03-01

    Purpose: Accurate target delineation of the nodal volumes is essential for three-dimensional conformal and intensity-modulated radiotherapy planning for endometrial cancer adjuvant therapy. We hypothesized that atlas-based segmentation ('autocontouring') would lead to time savings and more consistent contours among physicians. Methods and Materials: A reference anatomy atlas was constructed using the data from 15 postoperative endometrial cancer patients by contouring the pelvic nodal clinical target volume on the simulation computed tomography scan according to the Radiation Therapy Oncology Group 0418 trial using commercially available software. On the simulation computed tomography scans from 10 additional endometrial cancer patients, the nodal clinical targetmore » volume autocontours were generated. Three radiation oncologists corrected the autocontours and delineated the manual nodal contours under timed conditions while unaware of the other contours. The time difference was determined, and the overlap of the contours was calculated using Dice's coefficient. Results: For all physicians, manual contouring of the pelvic nodal target volumes and editing the autocontours required a mean {+-} standard deviation of 32 {+-} 9 vs. 23 {+-} 7 minutes, respectively (p = .000001), a 26% time savings. For each physician, the time required to delineate the manual contours vs. correcting the autocontours was 30 {+-} 3 vs. 21 {+-} 5 min (p = .003), 39 {+-} 12 vs. 30 {+-} 5 min (p = .055), and 29 {+-} 5 vs. 20 {+-} 5 min (p = .0002). The mean overlap increased from manual contouring (0.77) to correcting the autocontours (0.79; p = .038). Conclusion: The results of our study have shown that autocontouring leads to increased consistency and time savings when contouring the nodal target volumes for adjuvant treatment of endometrial cancer, although the autocontours still required careful editing to ensure that the lymph nodes at risk of recurrence are properly included in the

  3. Defining the "Hostile Pelvis" for Intensity Modulated Radiation Therapy: The Impact of Anatomic Variations in Pelvic Dimensions on Dose Delivered to Target Volumes and Organs at Risk in Patients With High-Risk Prostate Cancer Treated With Whole Pelvic Radiation Therapy.

    PubMed

    Yirmibeşoğlu Erkal, Eda; Karabey, Sinan; Karabey, Ayşegül; Hayran, Mutlu; Erkal, Haldun Şükrü

    2015-07-15

    The aim of this study was to evaluate the impact of variations in pelvic dimensions on the dose delivered to the target volumes and the organs at risk (OARs) in patients with high-risk prostate cancer (PCa) to be treated with whole pelvic radiation therapy (WPRT) in an attempt to define the hostile pelvis in terms of intensity modulated radiation therapy (IMRT). In 45 men with high-risk PCa to be treated with WPRT, the target volumes and the OARs were delineated, the dose constraints for the OARs were defined, and treatment plans were generated according to the Radiation Therapy Oncology Group 0924 protocol. Six dimensions to reflect the depth, width, and height of the bony pelvis were measured, and 2 indexes were calculated from the planning computed tomographic scans. The minimum dose (Dmin), maximum dose (Dmax), and mean dose (Dmean) for the target volumes and OARs and the partial volumes of each of these structures receiving a specified dose (VD) were calculated from the dose-volume histograms (DVHs). The data from the DVHs were correlated with the pelvic dimensions and indexes. According to an overall hostility score (OHS) calculation, 25 patients were grouped as having a hospitable pelvis and 20 as having a hostile pelvis. Regarding the OHS grouping, the DVHs for the bladder, bowel bag, left femoral head, and right femoral head differed in favor of the hospitable pelvis group, and the DVHs for the rectum differed for a range of lower doses in favor of the hospitable pelvis group. Pelvimetry might be used as a guide to define the challenging anatomy or the hostile pelvis in terms of treatment planning for IMRT in patients with high-risk PCa to be treated with WPRT. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Defining the “Hostile Pelvis” for Intensity Modulated Radiation Therapy: The Impact of Anatomic Variations in Pelvic Dimensions on Dose Delivered to Target Volumes and Organs at Risk in Patients With High-Risk Prostate Cancer Treated With Whole Pelvic Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yirmibeşoğlu Erkal, Eda, E-mail: eyirmibesoglu@yahoo.com; Karabey, Sinan; Karabey, Ayşegül

    2015-07-15

    Purpose: The aim of this study was to evaluate the impact of variations in pelvic dimensions on the dose delivered to the target volumes and the organs at risk (OARs) in patients with high-risk prostate cancer (PCa) to be treated with whole pelvic radiation therapy (WPRT) in an attempt to define the hostile pelvis in terms of intensity modulated radiation therapy (IMRT). Methods and Materials: In 45 men with high-risk PCa to be treated with WPRT, the target volumes and the OARs were delineated, the dose constraints for the OARs were defined, and treatment plans were generated according to themore » Radiation Therapy Oncology Group 0924 protocol. Six dimensions to reflect the depth, width, and height of the bony pelvis were measured, and 2 indexes were calculated from the planning computed tomographic scans. The minimum dose (D{sub min}), maximum dose (D{sub max}), and mean dose (D{sub mean}) for the target volumes and OARs and the partial volumes of each of these structures receiving a specified dose (V{sub D}) were calculated from the dose-volume histograms (DVHs). The data from the DVHs were correlated with the pelvic dimensions and indexes. Results: According to an overall hostility score (OHS) calculation, 25 patients were grouped as having a hospitable pelvis and 20 as having a hostile pelvis. Regarding the OHS grouping, the DVHs for the bladder, bowel bag, left femoral head, and right femoral head differed in favor of the hospitable pelvis group, and the DVHs for the rectum differed for a range of lower doses in favor of the hospitable pelvis group. Conclusions: Pelvimetry might be used as a guide to define the challenging anatomy or the hostile pelvis in terms of treatment planning for IMRT in patients with high-risk PCa to be treated with WPRT.« less

  5. Fast neutron measurements with 7Li and 6Li enriched CLYC scintillators

    NASA Astrophysics Data System (ADS)

    Giaz, A.; Blasi, N.; Boiano, C.; Brambilla, S.; Camera, F.; Cattadori, C.; Ceruti, S.; Gramegna, F.; Marchi, T.; Mattei, I.; Mentana, A.; Million, B.; Pellegri, L.; Rebai, M.; Riboldi, S.; Salamida, F.; Tardocchi, M.

    2016-07-01

    The recently developed Cs2LiYCl6:Ce (CLYC) crystals are interesting scintillation detectors not only for their gamma energy resolution (<5% at 662 keV) but also for their capability to identify and measure the energy of both gamma rays and fast/thermal neutrons. The thermal neutrons were detected by the 6Li(n,α)t reaction while for the fast neutrons the 35Cl(n,p)35S and 35Cl(n,α)32P neutron-capture reactions were exploited. The energy of the outgoing proton or α particle scales linearly with the incident neutron energy. The kinetic energy of the fast neutrons can be measured using both the Time Of Flight (TOF) technique and using the CLYC energy signal. In this work, the response to monochromatic fast neutrons (1.9-3.8 MeV) of two CLYC 1″×1″ crystals was measured using both the TOF and the energy signal. The observables were combined to identify fast neutrons, to subtract the thermal neutron background and to identify different fast neutron-capture reactions on 35Cl, in other words to understand if the detected particle is an α or a proton. We performed a dedicated measurement at the CN accelerator facility of the INFN Legnaro National Laboratories (Italy), where the fast neutrons were produced by impinging a proton beam (4.5, 5.0 and 5.5 MeV) on a 7LiF target. We tested a CLYC detector 6Li-enriched at about 95%, which is ideal for thermal neutron measurements, in parallel with another CLYC detector 7Li-enriched at more than 99%, which is suitable for fast neutron measurements.

  6. Fast discharge in a spherical cavity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Antsiferov, P. S., E-mail: Ants@isan.troitsk.ru; Dorokhin, L. A.

    2014-04-15

    The work is devoted to the study of the plasma, created by a fast discharge in a spherical cavity. The discharge was driven by an inductive storage with plasma erosion opening switch (dI/dt ∼10{sup 12} A/s). The plasma was produced in a spherical cavity (alumina, 11 mm diameter). Xe, Ar, and He at the pressure 80 Pa were used as working gases. The time evolution of the spatial structure and of extreme ultraviolet (EUV) spectra of the discharge plasma was studied by means of micro channel plate detector. The discharges with Xe and Ar resulted in the stable appearance of the spherically shapedmore » plasma with the diameter about 1–3 mm. The plasma emission in the EUV region lasts ∼500 ns. The EUV spectrum of Ar discharge at the moment of maximum of the electron temperature T{sub e} contains the lines of Ar X (ionization potential 478.7 eV), that indicates a value of T{sub e} in the range 50–100 eV. The mechanism of plasma appearance can be the cumulation of the convergent spherical shock wave, generated by fast heat deposition and magnetic pressure in working media near the inner surface of the discharge volume.« less

  7. Target motion tracking in MRI-guided transrectal robotic prostate biopsy.

    PubMed

    Tadayyon, Hadi; Lasso, Andras; Kaushal, Aradhana; Guion, Peter; Fichtinger, Gabor

    2011-11-01

    MRI-guided prostate needle biopsy requires compensation for organ motion between target planning and needle placement. Two questions are studied and answered in this paper: 1) is rigid registration sufficient in tracking the targets with an error smaller than the clinically significant size of prostate cancer and 2) what is the effect of the number of intraoperative slices on registration accuracy and speed? we propose multislice-to-volume registration algorithms for tracking the biopsy targets within the prostate. Three orthogonal plus additional transverse intraoperative slices are acquired in the approximate center of the prostate and registered with a high-resolution target planning volume. Both rigid and deformable scenarios were implemented. Both simulated and clinical MRI-guided robotic prostate biopsy data were used to assess tracking accuracy. average registration errors in clinical patient data were 2.6 mm for the rigid algorithm and 2.1 mm for the deformable algorithm. rigid tracking appears to be promising. Three tracking slices yield significantly high registration speed with an affordable error.

  8. Determining Acceptable Limits of Fast-Electron Preheat in Polar-Drive-Ignition Designs

    NASA Astrophysics Data System (ADS)

    Delettrez, J. A.; Collins, T. J. B.; Ye, C.

    2014-10-01

    In direct-drive-ignition designs, preheat by fast electrons created by the two-plasmon-decay instability at the quarter-critical density surface can increase the adiabat in the fuel layer and prevent ignition. Since eliminating the preheat entirely is not possible, it is necessary to understand the levels of preheat our targets can withstand before ignition is precluded. The current polar-drive point design is used as the basis for examining the effects of increasing the levels of fast electrons using the one-dimensional, radiation-hydrodynamics code LILAC. Once ignition failure is obtained, the design is then reoptimized using Telios, a downhill simplex method program, to recover ignition. This cycle is repeated until the design can no longer be reoptimized to produce ignition. Mappings of these final results provide insight into ignition failure caused by preheat and what specific target parameters serve to best stave off the effects of the preheat. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  9. A Hybrid Ion/Electron Beam Fast Ignition Concept

    NASA Astrophysics Data System (ADS)

    Albright, B. J.

    2009-11-01

    Fast ignition (FI) inertial confinement fusion is an approach to high-gain inertial fusion, whereby a dense core of deuterium/tritium fuel is assembled via direct or indirect drive and then a hot spot within the core is heated rapidly (over a time scale of order 10 ps) to ignition conditions by beams of fast charged particles. These particle beams are generated outside the capsule by the interaction of ultra-intense laser pulses with solid density targets. Most study of FI to date has focused on the use of electron [Tabak et al., Phys. Plasmas 1, 1696 (1994)] or ion [Fern'andez et al., Nuclear Fusion 49, 065004 (2009)] beams, however a hybrid approach involving both may have advantages. This paper will describe recent work in this arena. Work performed under the auspices of the U. S. Dept. of Energy by the Los Alamos National Security, Los Alamos National Laboratory. This work was supported by LANL Laboratory Directed Research and Development (LDRD).

  10. Novel regenerative large-volume immobilized enzyme reactor: preparation, characterization and application.

    PubMed

    Ruan, Guihua; Wei, Meiping; Chen, Zhengyi; Su, Rihui; Du, Fuyou; Zheng, Yanjie

    2014-09-15

    A novel large-volume immobilized enzyme reactor (IMER) on small column was prepared with organic-inorganic hybrid silica particles and applied for fast (10 min) and oriented digestion of protein. At first, a thin enzyme support layer was formed in the bottom of the small column by polymerization with α-methacrylic acid and dimethacrylate. After that, amino SiO2 particles was prepared by the sol-gel method with tetraethoxysilane and 3-aminopropyltriethoxysilane. Subsequently, the amino SiO2 particles were activated by glutaraldehyde for covalent immobilization of trypsin. Digestive capability of large-volume IMER for proteins was investigated by using bovine serum albumin (BSA), cytochrome c (Cyt-c) as model proteins. Results showed that although the sequence coverage of the BSA (20%) and Cyt-c (19%) was low, the large-volume IMER could produce peptides with stable specific sequence at 101-105, 156-160, 205-209, 212-218, 229-232, 257-263 and 473-451 of the amino sequence of BSA when digesting 1mg/mL BSA. Eight of common peptides were observed during each of the ten runs of large-volume IMER. Besides, the IMER could be easily regenerated by reactivating with GA and cross-linking with trypsin after breaking the -C=N- bond by 0.01 M HCl. The sequence coverage of BSA from regenerated IMER increased to 25% comparing the non-regenerated IMER (17%). 14 common peptides. accounting for 87.5% of first use of IMER, were produced both with IMER and regenerated IMER. When the IMER was applied for ginkgo albumin digestion, the sequence coverage of two main proteins of ginkgo, ginnacin and legumin, was 56% and 55%, respectively. (Reviewer 2) Above all, the fast and selective digestion property of the large-volume IMER indicated that the regenerative IMER could be tentatively used for the production of potential bioactive peptides and the study of oriented protein digestion. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Fasting and refeeding differentially regulate NLRP3 inflammasome activation in human subjects.

    PubMed

    Traba, Javier; Kwarteng-Siaw, Miriam; Okoli, Tracy C; Li, Jessica; Huffstutler, Rebecca D; Bray, Amanda; Waclawiw, Myron A; Han, Kim; Pelletier, Martin; Sauve, Anthony A; Siegel, Richard M; Sack, Michael N

    2015-11-03

    Activation of the NLRP3 inflammasome is associated with metabolic dysfunction, and intermittent fasting has been shown to improve clinical presentation of NLRP3 inflammasome-linked diseases. As mitochondrial perturbations, which function as a damage-associated molecular pattern, exacerbate NLRP3 inflammasome activation, we investigated whether fasting blunts inflammasome activation via sirtuin-mediated augmentation of mitochondrial integrity. We performed a clinical study of 19 healthy volunteers. Each subject underwent a 24-hour fast and then was fed a fixed-calorie meal. Blood was drawn during the fasted and fed states and analyzed for NRLP3 inflammasome activation. We enrolled an additional group of 8 healthy volunteers to assess the effects of the sirtuin activator, nicotinamide riboside, on NLRP3 inflammasome activation. In the fasting/refeeding study, individuals showed less NLRP3 inflammasome activation in the fasted state compared with that in refed conditions. In a human macrophage line, depletion of the mitochondrial-enriched sirtuin deacetylase SIRT3 increased NLRP3 inflammasome activation in association with excessive mitochondrial ROS production. Furthermore, genetic and pharmacologic SIRT3 activation blunted NLRP3 activity in parallel with enhanced mitochondrial function in cultured cells and in leukocytes extracted from healthy volunteers and from refed individuals but not in those collected during fasting. Together, our data indicate that nutrient levels regulate the NLRP3 inflammasome, in part through SIRT3-mediated mitochondrial homeostatic control. Moreover, these results suggest that deacetylase-dependent inflammasome attenuation may be amenable to targeting in human disease. ClinicalTrials.gov NCT02122575 and NCT00442195. Division of Intramural Research, NHLBI of the NIH.

  12. Assemblies with both target and fuel pins in an isotope-production reactor

    DOEpatents

    Cawley, W.E.; Omberg, R.P.

    1982-08-19

    A method is described for producing tritium in a fast breeder reactor cooled with liquid metal. Lithium target material is placed in pins adjacent to fuel pins in order to increase the tritium production rate.

  13. Fast analysis of radionuclide decay chain migration

    NASA Astrophysics Data System (ADS)

    Chen, J. S.; Liang, C. P.; Liu, C. W.; Li, L.

    2014-12-01

    A novel tool for rapidly predicting the long-term plume behavior of an arbitrary length radionuclide decay chain is presented in this study. This fast tool is achieved based on generalized analytical solutions in compact format derived for a set of two-dimensional advection-dispersion equations coupled with sequential first-order decay reactions in groundwater system. The performance of the developed tool is evaluated by a numerical model using a Laplace transform finite difference scheme. The results of performance evaluation indicate that the developed model is robust and accurate. The developed model is then used to fast understand the transport behavior of a four-member radionuclide decay chain. Results show that the plume extents and concentration levels of any target radionuclide are very sensitive to longitudinal, transverse dispersion, decay rate constant and retardation factor. The developed model are useful tools for rapidly assessing the ecological and environmental impact of the accidental radionuclide releases such as the Fukushima nuclear disaster where multiple radionuclides leaked through the reactor, subsequently contaminating the local groundwater and ocean seawater in the vicinity of the nuclear plant.

  14. Is fast food addictive?

    PubMed

    Garber, Andrea K; Lustig, Robert H

    2011-09-01

    Studies of food addiction have focused on highly palatable foods. While fast food falls squarely into that category, it has several other attributes that may increase its salience. This review examines whether the nutrients present in fast food, the characteristics of fast food consumers or the presentation and packaging of fast food may encourage substance dependence, as defined by the American Psychiatric Association. The majority of fast food meals are accompanied by a soda, which increases the sugar content 10-fold. Sugar addiction, including tolerance and withdrawal, has been demonstrated in rodents but not humans. Caffeine is a "model" substance of dependence; coffee drinks are driving the recent increase in fast food sales. Limited evidence suggests that the high fat and salt content of fast food may increase addictive potential. Fast food restaurants cluster in poorer neighborhoods and obese adults eat more fast food than those who are normal weight. Obesity is characterized by resistance to insulin, leptin and other hormonal signals that would normally control appetite and limit reward. Neuroimaging studies in obese subjects provide evidence of altered reward and tolerance. Once obese, many individuals meet criteria for psychological dependence. Stress and dieting may sensitize an individual to reward. Finally, fast food advertisements, restaurants and menus all provide environmental cues that may trigger addictive overeating. While the concept of fast food addiction remains to be proven, these findings support the role of fast food as a potentially addictive substance that is most likely to create dependence in vulnerable populations.

  15. A Vertically Lagrangian Finite-Volume Dynamical Core for Global Models

    NASA Technical Reports Server (NTRS)

    Lin, Shian-Jiann

    2003-01-01

    A finite-volume dynamical core with a terrain-following Lagrangian control-volume discretization is described. The vertically Lagrangian discretization reduces the dimensionality of the physical problem from three to two with the resulting dynamical system closely resembling that of the shallow water dynamical system. The 2D horizontal-to-Lagrangian-surface transport and dynamical processes are then discretized using the genuinely conservative flux-form semi-Lagrangian algorithm. Time marching is split- explicit, with large-time-step for scalar transport, and small fractional time step for the Lagrangian dynamics, which permits the accurate propagation of fast waves. A mass, momentum, and total energy conserving algorithm is developed for mapping the state variables periodically from the floating Lagrangian control-volume to an Eulerian terrain-following coordinate for dealing with physical parameterizations and to prevent severe distortion of the Lagrangian surfaces. Deterministic baroclinic wave growth tests and long-term integrations using the Held-Suarez forcing are presented. Impact of the monotonicity constraint is discussed.

  16. PACER -- A fast running computer code for the calculation of short-term containment/confinement loads following coolant boundary failure. Volume 2: User information

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sienicki, J.J.

    A fast running and simple computer code has been developed to calculate pressure loadings inside light water reactor containments/confinements under loss-of-coolant accident conditions. PACER was originally developed to calculate containment/confinement pressure and temperature time histories for loss-of-coolant accidents in Soviet-designed VVER reactors and is relevant to the activities of the US International Nuclear Safety Center. The code employs a multicompartment representation of the containment volume and is focused upon application to early time containment phenomena during and immediately following blowdown. PACER has been developed for FORTRAN 77 and earlier versions of FORTRAN. The code has been successfully compiled and executedmore » on SUN SPARC and Hewlett-Packard HP-735 workstations provided that appropriate compiler options are specified. The code incorporates both capabilities built around a hardwired default generic VVER-440 Model V230 design as well as fairly general user-defined input. However, array dimensions are hardwired and must be changed by modifying the source code if the number of compartments/cells differs from the default number of nine. Detailed input instructions are provided as well as a description of outputs. Input files and selected output are presented for two sample problems run on both HP-735 and SUN SPARC workstations.« less

  17. Effect of cooling rate on leucite volume fraction in dental porcelains.

    PubMed

    Mackert, J R; Evans, A L

    1991-02-01

    Prasad et al. (1988) have shown that slow cooling of dental porcelain produces increases in thermal expansion sufficient to make a compatible metal-porcelain system incompatible. The present study was undertaken to determine whether the increase in porcelain thermal expansion might be attributable to crystallization of additional leucite during slow cooling of the porcelain. Eight x-ray diffraction specimens for each of six commercial dental porcelains and for the Component No. 1 frit of the Weinstein and Weinstein (1962) and Weinstein et al. (1962) patents were fabricated and divided into two groups. Specimens in the first group (termed fast-cooled) were cooled in the conventional manner by removing them from the furnace at the maximum firing temperature immediately into room air. Specimens in the second group (termed slow-cooled) were cooled slowly by interrupting power to the furnace muffle and allowing them to cool inside the closed furnace. Quantitative x-ray diffraction was performed on the fast- and slow-cooled porcelain specimens with standards containing leucite volume fractions of 0.111, 0.223, 0.334, and 0.445. Unpaired, one-tailed t tests were performed on the fast- and slow-cool data, and a significant increase (p less than 0.05) in the amount of leucite (as a function of the slow cooling) was found for each of the porcelains. The increases in the leucite volume fractions resulting from the slow cooling ranged from a low of 8.5% to a high of 55.8%, with an average increase of 26.9%.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. GH signaling in human adipose and muscle tissue during 'feast and famine': amplification of exercise stimulation following fasting compared to glucose administration.

    PubMed

    Vendelbo, Mikkel H; Christensen, Britt; Grønbæk, Solbritt B; Høgild, Morten; Madsen, Michael; Pedersen, Steen B; Jørgensen, Jens O L; Jessen, Niels; Møller, Niels

    2015-09-01

    Fasting and exercise stimulates, whereas glucose suppresses GH secretion, but it is uncertain how these conditions impact GH signaling in peripheral tissues. To test the original 'feast and famine hypothesis' by Rabinowitz and Zierler, according to which the metabolic effects of GH are predominant during fasting, we specifically hypothesized that fasting and exercise act in synergy to increase STAT-5b target gene expression. Eight healthy men were studied on two occasions in relation to a 1 h exercise bout: i) with a concomitant i.v. glucose infusion ('feast') and ii) after a 36 h fast ('famine'). Muscle and fat biopsy specimens were obtained before, immediately after, and 30 min after exercise. GH increased during exercise on both examination days and this effect was amplified by fasting, and free fatty acid (FFA) levels increased after fasting. STAT-5b phosphorylation increased similarly following exercise on both occasions. In adipose tissue, suppressors of cytokine signaling 1 (SOCS1) and SOCS2 were increased after exercise on the fasting day and both fasting and exercise increased cytokine inducible SH2-containing protein (CISH). In muscle, SOCS2 and CISH mRNA were persistently increased after fasting. Muscle SOCS1, SOCS3, and CISH mRNA expression increased, whereas SOCS2 decreased after exercise on both examination days. This study demonstrates that fasting and exercise act in tandem to amplify STAT-5b target gene expression (SOCS and CISH) in adipose and muscle tissue in accordance with the 'feast and famine hypothesis'; the adipose tissue signaling responses, which hitherto have not been scrutinized, may play a particular role in promoting FFA mobilization. © 2015 European Society of Endocrinology.

  19. Differential Regulation of Thyroid Hormone Metabolism Target Genes during Non-thyroidal Illness Syndrome Triggered by Fasting or Sepsis in Adult Mice

    PubMed Central

    Fontes, Klaus N.; Cabanelas, Adriana; Bloise, Flavia F.; de Andrade, Cherley Borba Vieira; Souza, Luana L.; Wilieman, Marianna; Trevenzoli, Isis H.; Agra, Lais C.; Silva, Johnatas D.; Bandeira-Melo, Christianne; Silva, Pedro L.; Rocco, Patricia R. M.; Ortiga-Carvalho, Tania M.

    2017-01-01

    Fasting and sepsis induce profound changes in thyroid hormone (TH) central and peripheral metabolism. These changes affect TH action and are called the non-thyroidal illness syndrome (NTIS). To date, it is still debated whether NTIS represents an adaptive response or a real hypothyroid state at the tissue level. Moreover, even though it has been considered the same syndrome, we hypothesized that fasting and sepsis induce a distinct set of changes in thyroid hormone metabolism. Herein, we aimed to evaluate the central and peripheral expression of genes involved in the transport (MCT8/Slc16a2 and MCT10/Slc16a10), metabolism (Dio1, Dio2, and Dio3) and action (Thra and Thrb) of TH during NTIS induced by fasting or sepsis. Male mice were subjected to a 48 h period of fasting or cecal ligation and puncture (CLP)-induced sepsis. At the peripheral level, fasting led to: (1) reduced serum thyroxine (T4) and triiodothyronine (T3), expression of Dio1, Thra, Slc16a2, and MCT8 protein in liver; (2) increased hepatic Slc16a10 and Dio3 expression; and (3) decreased Slc16a2 and Slc16a10 expressions in the thyroid gland. Fasting resulted in reduction of Tshb expression in the pituitary and increased expression of Dio2 in total hypothalamus, arcuate (ARC) and paraventricular (PVN) nucleus. CLP induced sepsis resulted in reduced: (1) T4 serum levels; (2) Dio1, Slc16a2, Slc16a10, Thra, and Thrb expression in liver as well as Slc16a2 expression in the thyroid gland (3) Thrb and Tshb mRNA expression in the pituitary; (4) total leukocyte counts in the bone marrow while increased its number in peritoneal and pleural fluids. In summary, fasting- or sepsis-driven NTIS promotes changes in the set point of hypothalamus-pituitary-thyroid axis through different mechanisms. Reduced hepatic THRs expression in conjunction with reduced TH transporters expression in the thyroid gland may indicate, respectively, reduction in the peripheral action and in the secretion of TH, which may contribute to

  20. Differential Regulation of Thyroid Hormone Metabolism Target Genes during Non-thyoidal Illness Syndrome Triggered by Fasting or Sepsis in Adult Mice.

    PubMed

    Fontes, Klaus N; Cabanelas, Adriana; Bloise, Flavia F; de Andrade, Cherley Borba Vieira; Souza, Luana L; Wilieman, Marianna; Trevenzoli, Isis H; Agra, Lais C; Silva, Johnatas D; Bandeira-Melo, Christianne; Silva, Pedro L; Rocco, Patricia R M; Ortiga-Carvalho, Tania M

    2017-01-01

    Fasting and sepsis induce profound changes in thyroid hormone (TH) central and peripheral metabolism. These changes affect TH action and are called the non-thyroidal illness syndrome (NTIS). To date, it is still debated whether NTIS represents an adaptive response or a real hypothyroid state at the tissue level. Moreover, even though it has been considered the same syndrome, we hypothesized that fasting and sepsis induce a distinct set of changes in thyroid hormone metabolism. Herein, we aimed to evaluate the central and peripheral expression of genes involved in the transport (MCT8/ Slc16a2 and MCT10/ Slc16a10 ), metabolism ( Dio1, Dio2 , and Dio3 ) and action ( Thra and Thrb ) of TH during NTIS induced by fasting or sepsis. Male mice were subjected to a 48 h period of fasting or cecal ligation and puncture (CLP)-induced sepsis. At the peripheral level, fasting led to: (1) reduced serum thyroxine (T 4 ) and triiodothyronine (T 3 ), expression of Dio1, Thra, Slc16a2 , and MCT8 protein in liver; (2) increased hepatic Slc16a10 and Dio3 expression; and (3) decreased Slc16a2 and Slc16a10 expressions in the thyroid gland. Fasting resulted in reduction of Tshb expression in the pituitary and increased expression of Dio2 in total hypothalamus, arcuate (ARC) and paraventricular (PVN) nucleus. CLP induced sepsis resulted in reduced: (1) T 4 serum levels; (2) Dio1, Slc16a2, Slc16a10, Thra , and Thrb expression in liver as well as Slc16a2 expression in the thyroid gland (3) Thrb and Tshb mRNA expression in the pituitary; (4) total leukocyte counts in the bone marrow while increased its number in peritoneal and pleural fluids. In summary, fasting- or sepsis-driven NTIS promotes changes in the set point of hypothalamus-pituitary-thyroid axis through different mechanisms. Reduced hepatic THRs expression in conjunction with reduced TH transporters expression in the thyroid gland may indicate, respectively, reduction in the peripheral action and in the secretion of TH, which may